January Democratic debate live updates: Six candidates face off in Des Moines

The tone from Team Sanders in the spin room tonight was that it is time to move on from the Warren controversy. 

"You have two candidates, they got different recollections of the event. Voters are gonna have to look at those and make their own decision," Senior Advisor Jeff Weaver told NBC News. 

Neither Weaver nor top surrogate Nina Turner spoke to Sanders after the debate about the awkward exchange between Sanders and Warren at the conclusion of the debate where it appears Warren denied Sanders a handshake. 

NBC News has reached out to the campaign for an understanding of what was said and what actually occurred. Turner said while she was not sure what was said, it was clear their conversation was not pleasant. 

The fight for the heart and soul of the Democratic Party was on display Tuesday night in Des Moines, with moderate and progressive candidates clashing on a range of issues — from trade to troops in the Middle East — during the final debate before the Iowa caucuses.

With just six candidates on stage Tuesday night at the CNN/Des Moines Register debate — down from the initial 20 contenders divided over two nights at the field's first faceoff last year — the contenders had more space to let their policy differences come into sharper focus. But despite rising tensions in recent days, they mostly avoided lobbing personal attacks at each other.

Less than a month before Iowa voters weigh in on a 2020 Democratic contest that’s become a virtual four-way dead heat, here's who held their ground — and who might have spent their last night on a primary season debate stage.

Sanders exaggerated data points about the current American health care system in his pitch for "Medicare for All" on Tuesday night.

"First of all, what Joe forgets to say is when you leave the current system as it is, what you are talking about are workers paying, on average, 20 percent of their incomes for health care," Sanders said, referring to former Vice President Biden. "That is insane. You've got 500,000 people going bankrupt because they cannot pay their medical bills. We're spending twice as much per capita on health care as do the people of any other country."

Let's dig in.

• Americans are not typically spending 20 percent of percent of incomes on health care, according to federal consumer expenditure data from 2018, as well as research on the issue. To be sure, there are some people for whom this is true — particularly in Medicare families — but it's not correct to describe the nation this way. 
• The U.S. spends twice as much as many — but not all — developed nations on health care, according to data from the intergovernmental Organization for Economic Co-operation and Development (OECD). It’s not twice as much as "any other country," however.

As for the half a million medical bill bankruptcies per year, The Washington Post dug into the data point last year and rated it "Three Pinocchios" — though Sanders' campaign and researchers of the American Journal of Public Health editorial his campaign told The Post he relied on for the statistic disputed the rating. Read the paper's deep dive here. 

• With 19 attacks in 17 minutes of talking time Amy Klobuchar made the most attacks, averaging more than one attack every minute spoken.
• Elizabeth Warren had the most speaking time with more than 19 minutes.
• Tom Steyer spoke the least, he had 10 minutes of talking time.
• Six candidates was the fewest candidates on stage yet in these debates.
• Bernie Sanders and Pete Buttigieg were attacked the most, with five attacks on each.
• Candidates attacked Donald Trump 45 times, Mitch McConnell zero times, Wall Street and corporations 13 times, and the “ultra-rich” three times.

DES MOINES, Iowa — The nonaggression pact between Sen. Bernie Sanders of Vermont and Sen. Elizabeth Warren of Massachusetts faced its most difficult test and held — at least for now.

The two progressive senators de-escalated a tense round of tit-for-tat exchanges between their presidential campaigns on the debate stage here Tuesday night over the charged issues of gender and electability.

Aides and supporters of both senators, who have more or less remained allies even while running against each for the 2020 Democratic presidential nomination, had accused each other of dirty tricks and lying in recent days after a series of leaks to the media, culminating in Warren saying in a statement that Sanders once told her he didn't think a woman could win the presidency.

But when the topic came up during a debate hosted by CNN, both sought to set the issue aside and move on, even as Sanders once again denied telling Warren a woman couldn't win during a one-on-one meeting in 2018.

Read the full story.

Candidates attacked President Donald Trump 45 times in the two hours and ten minutes of tonight's debate. That's more attacks directed at Trump in any debate except Night 2 of the July 2019 Democratic debate.

See the full numbers at our seventh Democratic debate attack tracker here.

"Back in 1986, I introduced the first climate change bill — and check PolitiFacts, they said it was a game changer. I have been fighting this for a long time," Biden said during Tuesday's debate.

While Biden did introduce one of the first pieces of climate change legislation in the Senate in 1986 and again in 1987, as PolitiFact noted, it wasn't the first time Congress had considered the issue.

A Democratic senator named Al Gore introduced a non-binding resolution in 1985 asking the president to study greenhouse gas emissions, PolitiFact said. The New York Times covered his push with the headline, “Action Is Urged to Avert Global Climate Shift," and reported that Gore said his bill would call for ''an international year of scientific study of the greenhouse effect and would request that the President take steps to begin this worldwide cooperative investigation.''

Meanwhile:

And that’s a wrap, folks. Here are the (not verbatim) closing statements of each candidate summed up, edited for length and clarity in order of speaking.

Klobuchar: This election is about you. It is about your health care, your schools and your lives. It’s about racial justice and climate change and gun safety. If you are tired of the extremism and noise and nonsense in Washington, I am your candidate. 

Steyer: The American people are my teammates. I can prepare to take on Trump on the debate stage and take him down on the economy.

Buttigieg: We cannot take the risk of trying to confront this president with the same Washington mindset. If you are tired of the spectacle of division and dysfunction, join me to turn the page on our policies and summon the courage to break from the past. 

Warren: I see this as our moment in history, our moment when no one is left on the sidelines — those living in poverty, trans women of color, black infant mortality, climate change, student loan debt. Hope and courage, that is how I will make you proud as your nominee, and as the first woman president. 

Sanders: This is the moment when we have to think big, not small. This the moment to have the courage to take on the 1 percent and corporate greed and create a government that works for all and not just the 1 percent. 

Biden: Character is on the ballot, and that's not what Trump is spewing out with his xenophobia and racism. We have to restore America’s soul. It is in jeopardy under this president. We have to regain the respect of the world. We are in a position to do so right now. 

Biden made what is really his case for perceived "electability" at the end of Tuesday’s debate.

Biden said that even though he’s been the “object of Trump’s affection” for months — hinting at Trump’s push for Ukraine to probe Biden and his son Hunter, which led to the president’s impeachment — his poll numbers have remained strong and he has maintained his position at the top of the primary field, bolstering his case that he will be able to take on Trump in the fall.

The former vice president added that he currently has more African American support than his Democratic rivals, and that has strengthened his primary bid and has yet to waver in the polls.

Billionaire philanthropist Tom Steyer is sporting a unique accessory at today’s debate — markings on his hand that have many on social media raising their eyebrows. 

The design is called the “Jerusalem Cross,” and as Steyer wrote on Facebook late last year, he does it “every day to remind myself that ultimately, the truth always wins.” 

Steyer explained the design in a text exchange published on Buzzfeed, adding that he’s drawn it on his hand each day “for a while now.”

Steyer did not come to play about Buttigieg’s age and experience.

Over the course of two hours on the debate stage, Steyer managed two opaque but critical references to Buttigieg's youth and, by implication, inexperience. First, Steyer described Buttigieg as a man about the same age as Steyer’s. children. Then, Steyer described Buttigieg as someone with about three years of experience at the consulting firm McKinsey & Company to his 30 years of experience operating an international business.

Buttigieg’s retort to the second: Steyer’s description “demoted him” from a McKinsey associate to a mere consultant and that, by the way, wasn’t the “biggest part of his career.”

Buttigieg’s political experience, leading a town of around 100,000 people has been a persistent line of attack perused by other candidates as his standing in the polls ebbed and peaked.

Elizabeth Warren has talked about her Aunt Bee, a trusted relative who swooped in when a young Elizabeth Warren faced the conundrum of trying to find and afford decent child care or curtail her career. The moral of the story: Aunt Bee made Warren’s career possible, but millions of parents don’t have an Aunt Bee.

Tonight, Warren added another element to her child care plank. Today, it’s women of color doing a lot of this essential labor for very little pay. Across the country about 1.2 million people — most of them women — are providing the child care that today makes other people’s careers possible but on average make about $11 an hour, or roughly $23,000 a year in 2018, according to federal data. Among them, about 44 percent are women of color. 

Many working in private homes and child care centers with small staffs have few, if any basic labor protections, such as overtime pay, paid time off, health insurance or legal avenues to address workplace harassment and discrimination. 

An hour and a half into the debate and Amy Klobuchar is doing the most attacking (16 attacks), and Bernie Sanders is the candidate on the stage getting attacked the most (5 attacks).

Sanders and Elizabeth Warren had stayed away from attacking each other in previous debates, but tonight that ended.

And, yes, it's nothing new that President Donald Trump is the most-attacked person in the debate.

See the latest numbers on candidate attacks.

“Have you no sense of decency, sir?”

Klobuchar, answering a question about Trump and impeachment, referred to an exchange from Sen. Joseph McCarthy’s infamous efforts to identify communists in the U.S. in the 1950s.

Fed up with McCarthy’s accusations, U.S. Army special counsel Joseph Welch asked the question, which you can watch below.

When asked if an acquittal in Trump’s Senate impeachment trial would embolden him in the general election, Biden said that the American people know Trump hasn’t done his job and that after beating him in November, he would still work to unite the country.

"There's no choice but for Nancy Pelosi and the House to move. He has in fact committed impeachable offenses," Biden said of Trump. "And I did my job. The question is whether or not he did his job. And he hasn't done his job. So it doesn't really matter whether or not he is going after me, I have to be in a position that I think about the American people.

"I can't hold a grudge. I have to be able to not only fight but also heal."

Yes, the candidates are rehashing many of the same arguments about health care that we’ve heard before.

But there’s a reason that health care comes up for so long in every debate: Democratic voters consistently say that it’s their top issue.  

That’s certainly the case in Iowa, where tonight’s debate is taking place. Last week’s Des Moines Register/CNN poll found that 68 percent of Democratic voters in the state called health care “extremely important” to their vote choice in the caucuses, with another 25 percent calling it “important.”

With the exception of climate change, other issues received significantly less attention from voters.

Just 52 percent called the economy “extremely” important to their vote choice, and just 25 percent named impeachment as “extremely” important to them.

A constant refrain over the course of all the Democratic debates among candidates opposed to universal public health care: Americans are happy with their health insurance the way it is.

The details are a little more complicated. For about 156 million Americans, their employers provide their health insurance. And most employees do say they are satisfied with those plans, according to a May 2019 Kaiser Family Foundation/Los Angeles Times survey of Americans with employer-provided health insurance. 

But 40 percent of those polled also said they had real difficulty paying medical bills, affording their premiums, deductibles and copays. And 51 percent said they or a relative have skipped or postponed medical care or medications they needed and even relied on home remedies because of cost. 

Midway into tonight's debate, President Donald Trump has been attacked as many times as in the entire September Democratic debate. Amy Klobuchar accounts for 11 of those 28 attacks, and Bernie Sanders  five.

An hour into the seventh Democratic debate, Bernie Sanders leads all candidates in talking time. After a strong start, Joe Biden has dropped back into the middle of the pack.

Follow the NBC News talking-time tracker here.

Chris Matthews deserves a shout-out after Elizabeth Warren seemed to snag a chapter — “Hang a Lantern on Your Problem” — out of the MSNBC’s host’s seminal political book “Hardball.” The phrase means it’s better to call attention to your own potential political vulnerabilities than let an opponent hammer you on them first.

Warren said the question of whether a woman can win the presidency has been swirling in Democratic circles throughout the primary — in a way that suggests a woman would lose — and that the candidates shouldn’t “deny” that. 

The idea is nonsense, she argued, noting she and Sen. Amy Klobuchar, D-Minn., are “the only people on this stage who have won every single election they've been in.”

Her rivals agreed with her that a woman can with the presidency. That makes it harder for any of them to suggest a woman can’t win going forward and may inoculate her and Klobuchar from voter fears that nominating a woman in 2020 will result in the same outcome as it did in 2016. Not the hardball viewers might have expected after Warren tussled with Sanders over whether he’d told her a woman couldn’t win the White House, but “Hardball” nonetheless.

In responding to concerns that a woman cannot win the presidency, Sen. Elizabeth Warren argued that Trump’s presidency had produced many things including a wave of women elected to public office.

In 2018, the first midterm election cycle after Donald Trump secured the White House, voters sent a record number of women to Congress: 117. Today, women make up about 20 percent of the U.S. House and Senate.

It’s not the first time that women have seen vast public office gains amid gender-related controversy. After Americans watched an all-male Senate Judiciary committee investigate Anita Hill’s sexual harassment allegations, voters elected so many women to federal public office that 1992 became known as “The Year of The Woman.” That year, California became the first state with an all-female Senate delegation.

After Warren said "the only person on this stage who has beaten an incumbent Republican any time in the past 30 years is me," Sanders countered with a fact check: He beat a Republican incumbent in Vermont in 1990.

The devil’s in the details — especially when it comes to fact checking — and Sanders is technically correct. He defeated Rep. Peter Smith, a Republican, in November 1990. So ... 29 years and a couple of months ago.

It’s hard to cut through the noise on Twitter, especially on debate night. Well, Michael Bloomberg’s social team sure is trying. 

They’ve sent out a variety of odd tweets, none weirder than this one:

Elizabeth Warren declared midway into tonight's debate she wasn't here to attack Bernie Sanders... then minutes later she attacked Sanders, twice.

She and Sanders had been hands-off with each other: Up until tonight Warren had attacked Sanders zero times and Sanders had attacked Warren zero times.

Follow along with the NBC News debate attack tracker.

Warren was given the chance to respond to Sanders' assertion that he did not tell her in a one-on-one 2018 meeting that a woman couldn’t be elected president, which she had earlier claimed he did.

“I disagreed,” Warren said of her thoughts on their reported 2018 discussion. “Bernie is my friend, and I am not here to try to fight with Bernie. But, look, this question about whether or not a woman can be president has been raised and it's time for us to attack it head on. And I think the best way to talk about who can win is by looking at people's winning record. So, can a woman beat Donald Trump?”

“Look at the men on this stage: Collectively, they have lost 10 elections. The only people on this stage who have won every single election that they've been in are the women: Amy and me. And the only person on this stage who has beaten an incumbent Republican anytime in the past 30 years is me.”

Sanders responded that he had defeated a Republican incumbent in 1990, to which Warren responded that she placed her timeline within 30 years. Sanders’ 1990 election is months short of being 30 years ago.

Warren later expanded upon her earlier answer, saying: "I do think it's the right question, how do we beat Trump? And here's the thing. Since Donald Trump was elected, women candidates have outperformed men candidates in competitive races.”

“Back in the 1960s people asked, 'Could a Catholic win?'” she added. “Back in 2008 people asked if an African American could win. In both times the Democratic Party stepped up and said yes, got behind their candidate and we changed America. That's who we are."

Sanders, for his part, told moderators that he believes a woman can win the White House.

Sanders again denied telling Warren that a woman cannot be elected president. He said that the attacks are what Trump and the media want and that he plans to work to elect whoever wins the nomination if he doesn’t.

The candidates aren’t waiting for climate questions to bring up the issue.

Sanders, Warren, Buttigieg and Steyer have all brought up climate change in reference to non-climate questions. It’s notable because global warming can sometimes get lost in the shuffle or only get discussed in reference to specific questions.

But tonight we’re hearing how climate is an intersectional issue, particularly when it comes to the country and the world’s economic future.

The beginning of the final Democratic debate before the Iowa caucuses zeroed in on foreign policy, the decision to use military force, and how the United States deals with its adversaries.

While the topic included a refresher on Joe Biden’s onetime support for the war in Iraq — courtesy of Bernie Sanders — the heavy focus on foreign policy more generally could be helpful to Biden, who is the candidate most trusted on foreign policy by Democratic voters, according to a recent CNN poll.

CNN found in its November national poll that 48 percent of Democratic voters called Biden the most capable candidate to handle foreign policy. The contenders with the next highest level of trust were Sanders, at just 14 percent, and Warren, at just 11 percent.

Early into tonight's debate, Joe Biden has gotten the most talking time. This is opposite the position he was in early in the December 2019 Democratic debate.

Sanders and Warren drew their first significant distinction of the night — and it was on trade. 

(Yeah, not what people were expecting heading into the night.)

Sanders said he doesn’t support USMCA, Trump's NAFTA replacement, because of the impact it will have on the environment, even if big labor is supportive. 

But Warren said the agreement would be an improvement on NAFTA, calling it a "modest improvement." She also highlighted past deals she was against.

BUT... neither candidate directly criticized the others' position, even when given the opportunity.

Sanders has been a vocal critic of free trade for years, mostly because of the toll it has taken on U.S. workers.

But tonight, he emphasized the impact that outsourcing can have on the climate. And when moderator Brianne Pfannenstiel told him the debate will touch on climate change later but the current question is about trade, Sanders immediately responded: “Well, they are the same in this issue.”

Sanders talked up his well-known opposition to the Iraq War on the debate stage Tuesday, but he omitted his repeated support for a regime change in Iraq in the years leading up to that war and his mixed record on war and peace. Sanders voted for the Iraq Liberation Act and backed President Bill Clinton's airstrikes in 1998 and advocated for regime change in the country.

“Mr. Speaker, Saddam Hussein is a brutal dictator who should be overthrown, and his ability to make weapons of destruction must be eliminated,” he said on the Senate floor in December 1998.

As NBC News' Jon Allen noted earlier today, Sanders has said his 2001 vote to authorize war in Afghanistan was "wrong." He has repeatedly attacked Biden for voting in favor of the Iraq War, a vote that Biden has similarly characterized as a mistake. 

Biden said that in his administration he would work with China to pressure North Korea and would not meet with North Korean leader Kim Jong-Un, who previously called the former vice president a rabid dog that should be beaten with a stick.

Sanders then chimed in: "Other than that, you like him?" This drew laughter from the audience.

Biden responded: "Other than that, I like him, and he got a love letter from Trump right after that."

Bernie Sanders tied old wars to the current debate over war powers with a message aimed at the conscience and collective memory of the Democratic Party’s left wing.

He fears, he said, that President Donald Trump is the latest in a line of commanders in chief — following Lyndon Johnson, Richard Nixon and George W. Bush — who will abuse his bully pulpit to deceive the American public about bloody and costly wars.

“What we have to face as a nation is that the two great foreign policy disasters of our lifetimes were the war in Vietnam and the war in Iraq,” he said. “Both of those wars were based on lies. And right now, what I fear very much is we have a president who is lying again and could drag us into a war that is even worse than the war in Iraq.”

It was a message Sanders was intent on delivering: He delayed answering a different question from moderator Wolf Blitzer to pause, zoom out and explain how he thinks Vietnam and Iraq are connected to the current clash over war powers.

This is a two-hour debate, and we’re a quarter through it. And, so far, it’s a different kind of debate. 

Questions from the moderators have centered on foreign policy: troops in the Middle East, Iran’s nuclear efforts and how to handle North Korea.

Foreign policy had not dominated any of the previous Democratic debates so far, but it's not hard to see why it came to the forefront: the recent events in Iran and Iraq.

At the December debate, in response to a question about what to do about continued U.S. involvement in Afghanistan, Sanders said he was wrong to support the initial military action — and acknowledged the stand taken by Barbara Lee.

Lee, a Democratic representative from California, has been an ardent anti-war advocate and was the only member of Congress to vote against military action after 9/11.

In response to a question about whether to pull U.S. troops out of the Middle East, Warren stands out for calling for the removal of combat troops.

Biden and Klobuchar hold that the U.S. needs to maintain a presence. Sanders and Buttigieg don’t offer definitive answers.

Overall, the candidates didn't demonstrate significant differences between on military policy in the Mideast, with the exception of whether to leave some troops in the area. And even if you pull troops out, it’s relatively easy today to send them back fairly quickly.

Throughout tonight's debate, the NBC News Data / Graphics team is tracking the numbers behind the debate: How much speaking time has each candidate gotten, and which candidates are attacking one another (and Donald Trump) the most.

Fifteen minutes into the debate Bernie Sanders is leading all candidates in speaking time and Donald Trump is the only person candidates are attacking.

Klobuchar and Buttigieg engaged in some heated exchanges in the previous debate regarding experience. Blitzer wastes no time in bringing that up, but Klobuchar dodges it.

"I’ve been very clear that I respect the mayor’s experience very much in the military," she said. " I just have a different experience. I’ve been in the U.S. Senate for over 12 years."

Previous debates were in large halls and had more candidates. This time, with six candidates in a smaller venue at Drake University, there’s already a cozier feeling to the scene.

The seventh Democratic debate kicks off with a foreign policy question: Why the candidates think they're best prepared to be commander in chief. Sen. Bernie Sanders, I-Vt., was given the opportunity to respond first.

Sanders said he's fit to be commander in chief because he voted against the war in Iraq when he was a representative in the House. He said he would lead through diplomacy rather than war. 

MILWAUKEE — At a campaign rally here Tuesday night just ahead of the Democratic debate, President Donald Trump referred to the latest rift between Elizabeth Warren and Bernie Sanders. 

“I don't believe that Bernie said that, I really don't,” Trump said of reports that Sanders told Warren in a private conversation that a woman could not win the presidency. 

“A woman can win for president,” Trump said, laughing at a member in the crowd who shouted “Melania!”

There's at least one candidate who will not be getting into the fray at all between Warren and Sanders: Biden. Even though he will literally be standing between both of them, three Biden aides say that the former VP will do his best to stay out of the spat between the two most progressive candidates in the race.

Biden again avoided reporters’ questions about the Warren-Sanders feud at a stop in Des Moines on Monday night (he hasn’t held a formal gaggle with his traveling press corps in weeks). And his campaign opted not to hold its usual debate day briefing with reporters Tuesday in part to avoid being drawn into the fray.

Aides say Biden is prepared, however, to once again answer charges about his Iraq War record since they expect Sanders to bring it up during the debate. In recent weeks, Biden has been quick to dismiss Sanders’ jabs about the former vice president on Iraq and Biden’s inability to excite the party. Though Biden has largely avoided responding to Sanders directly, he has offered more than a few sarcastic asides lately, which he hasn’t done as much with other Democratic opponents in the race.

Biden really hasn’t gone after Warren in recent weeks, besides pointing out generally that some candidates like her have attacked him for what they believe is an unrealistic ability to unite the party.

A New York Times graphic for tonight's debate caught a bit of attention on Twitter for its surprising resemblance to Weezer's classic debut album "Weezer," which is better known as the Blue Album. 

Let's hope this means the next debate is as good as "Pinkerton."

Here's what you need to know about the brewing tensions between Warren and Sanders:

Warren on Sunday called on Sanders to turn his campaign "in a different direction" after it reportedly provided talking points to its volunteers instructing them to paint Warren as the candidate of elites in conversations with voters.

Read more about that here.

Warren on Monday said that in 2018 told her that he didn't think a woman could win the 2020 election — a statement the Sanders campaign had blasted as "a lie" earlier in the day.

"Bernie and I met for more than two hours in December 2018 to discuss the 2020 election, our past work together and our shared goals," Warren said in a statement. "Among the topics that came up was what would happen if Democrats nominated a female candidate. I thought a woman could win; he disagreed."

Read more about that here.

Yang isn't on the debate stage tonight, but he had some good news: an endorsement from comedian Dave Chappelle.

You might be wondering just who Brianne Pfannenstiel is, according to Google.

Searches for Pfannenstiel are up a whopping 4,200 percent (granted from what is probably a very small initial amount) ahead of tonight's debate. 

Pfannenstiel, 31, is the top political correspondent for The Des Moines Register and a moderator for the debate, alongside CNN's Wolf Blitzer and Abby Phillip. 

As for how the candidates stack up against each other in terms of Google searches, Bernie Sanders currently retains the top spot, followed by Warren, Biden, Buttigieg and Steyer. 

Sen. Bernie Sanders has stepped up an undeclared war on his top rivals for the Democratic presidential nomination — and left himself open to counterattack — because it's do-or-die time for him.

Sanders, I-Vt., and his supporters are tangling with former Vice President Joe Biden over foreign policy, trade and race, and with Sen. Elizabeth Warren, D-Mass., over policy purity, elitism and whether he said a woman can't win the presidency. The skirmishes rile up his base at the expense of alienating other Democrats.

While that's a strategy that makes more sense here and in other early primary states, where a relatively small but committed army of supporters can deliver victory, it risks a severe backlash now or over the long run.

Yet Sanders' best shot starts with his taking the Feb. 3 Iowa caucuses, following up with wins in New Hampshire and Nevada and riding a wave to a majority of delegates before the party's convention in Milwaukee in July.

That is, he needs to light a fire now. The question is whether he can control the blaze.

Read more here.

DES MOINES, Iowa — This isn't how the home stretch before the Iowa caucus was supposed to go.

Sen. Bernie Sanders, I-Vt., seemed to have been telegraphing a willingness to take on former Vice President Joe Biden for his judgment on the Iraq War, amid the escalating tensions with Iran. That was the singular focus until the conflict between Sanders and fellow progressive Sen. Elizabeth Warren bubbled into a fever pitch in the days leading up to the debate on Tuesday night here.

The very public rift marks a sea change in a winnowing Democratic field, less than three weeks before Iowans are set to caucus on Feb. 3.

And the crux of the Sanders-Warren conversation — about whether a woman can beat Trump — also highlights uncomfortable questions about perceived "electability" and brings about the specter of Hillary Clinton's 2016 loss. In conversations with a dozen Democratic operatives and aides, there appears to be little appetite for, and much hand-wringing over, these topics of conversation — on Clinton, on 2016 or on electability and gender.

Read more here.

The seventh Democratic presidential debate is set for Tuesday night, and it will be the smallest — and least diverse — debate to date.

The field of candidates has been shrinking, and the front-runners' campaigns have been taking on a tougher tone with one another, with even old friends Bernie Sanders and Elizabeth Warren butting heads.

The debate is the last before the Iowa caucus on Feb. 3. The two candidates who've been sniping at each other the most in recent weeks, former Vice President Joe Biden and Sanders, the independent senator from Vermont, will be standing side by side on center stage.

Here's what you need to know.