Making their closing arguments to voters in the last televised debate before the Iowa caucuses, the six top Democratic candidates did their best to explain how they would overcome the biggest challenges facing their campaign.
Former South Bend, Indiana, Mayor Pete Buttigieg insisted that he would be able to overcome his scant support among black voters. Vermont Sen. Bernie Sanders argued that his embrace of socialism would not be off-putting to a broader electorate. And businessman Tom Steyer said it would not be his wealth that was important to voters, but rather his ability to take on Trump on the issue that matters most to them: the economy.
But it was Sen. Elizabeth Warren's answer about she would overcome the skepticism of voters who do not believe a woman can win the presidency that won the night.
"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," the Massachusetts senator said.
"Can a woman beat Donald Trump? Look at the men on this stage. Collectively, they have lost 10 elections," she added. "The only people on this stage who have won every single election that they've been in are the women: Amy and me," she said, referring to the only other woman onstage: Minnesota Sen. Amy Klobuchar.
"So true," Klobuchar chimed in from the other side of the stage.
The Minnesota senator pointed to her winning record in the Midwest.
"I have won every race, every place, every time. I have won in the reddest of districts. I have won in the suburban areas, in the rural areas," she said.
The exchange came after Warren had affirmed what four sources told CNN: Sanders told her at that private dinner that a woman could not win. But on Tuesday night, Sanders once again insisted he never made that statement and said he would support whoever ends up being the Democratic nominee.
Warren had also noted she was the only person onstage who had beaten an incumbent Republican in the past 30 years.
"Just to set the record straight, I defeated an incumbent Republican running for Congress," Sanders said when his turn came. Warren pressed him on when that was and he said 1990.
"Wasn't that 30 years ago?" Warren asked after appearing to do the math in her head. "I was the only one who's beaten an incumbent Republican in 30 years."
"Well, 30 years ago is 1990, as a matter of fact," Sanders replied.
Iran dominates opening stages
The debate started with the candidates tangling over who was best positioned to keep the country safe as they face voters who are increasingly anxious about another conflict in the Middle East after President Donald Trump ordered the targeted killing of Iranian commander Qasem Soleimani.
During the first few moments of the debate, Sanders faulted former Vice President Joe Biden for voting in 2002 to authorize the use of force in Iraq while he was a senator for Delaware. Sanders noted that he and Biden listened to the same intelligence from the administration of former President George W. Bush claiming that Saddam Hussein had weapons of mass destruction, but they voted differently on the Iraq War Resolution.
"The war in Iraq turned out to be the worst foreign policy blunder in the modern history of this country," Sanders said.
He added, "Joe and I listened to what (former Vice President) Dick Cheney and George Bush and (Secretary of Defense Donald) Rumsfeld had to say. I thought they were lying. I didn't believe them for a moment. I took to the floor. I did everything I could to prevent that war. Joe saw it differently."
Biden immediately noted that he made a mistake in voting for the Iraq War Resolution, but he emphasized the fact President Barack Obama tasked him as vice president with withdrawing the US from that conflict.
"I said 13 years ago it was a mistake to give the President the authority to go to war if, in fact, he couldn't get inspectors into Iraq to stop what was thought to be the attempt to get a nuclear weapon. It was a mistake," Biden said Tuesday night. But once Obama was elected, he said, "he turned to me and asked me to end that war."
"We should not send anyone anywhere unless the overwhelming vital interests of the United States are at stake. They were not at stake there, they were not at stake in Iraq. And it was a mistaken vote," Biden continued. "But I think my record overall on everything we've done has been—I'm prepared to compare it to anybody's on this stage."
The Iraq War has created a bind for the former vice president because, at a time of heightened tensions with Iran, he has argued that his decades of foreign policy experience in the Senate and as vice president have made him the most prepared candidate to handle crises abroad.
Sanders, Biden, Warren and Buttigieg are tightly clustered at the top of the Democratic field in recent polling. In interviews, Iowa voters have expressed a profound sense of indecision -- driven largely by the size of the field and what they perceive as the complexity of defeating Trump in November.
Many Iowa voters who are leaning toward Biden have noted his strength in the foreign policy arena, particularly his long-standing relationships with foreign leaders. The former vice president sought to highlight that quality on Tuesday night by touting that he was tasked with bringing the troops from the Iraq War home.
But his rivals, including former South Bend, Indiana, Mayor Pete Buttigieg have rejected that argument as he has batted away questions about his own relative inexperience in government. As a veteran in the US Navy Reserve who served one tour in Afghanistan in 2014, Buttigieg has called Biden's vote authorizing military force in Iraq "the worst foreign policy decision made by the United States in my lifetime."
On Tuesday night, Buttigieg highlighted his military experience but did not immediately attack Biden. instead he pivoted instead to an attack on President Donald Trump.
"The very President who said he was going to end endless war, who pretended to have been against the war in Iraq all along -- although we know that's not true -- now has more troops going to the Middle East," Buttigieg said.
He recalled how one of his fellow lieutenants had to gather the strength to leave his one-and-a-half-year-old son, who had no idea that his father was leaving for war.
"That is happening by the thousands right now, as we see so many more troops sent into harm's way. And my perspective is to ensure that that will never happen when there is an alternative as commander in chief," Buttigieg said.
At the same time Buttigieg insisted that he would not allow Iran to get a nuclear weapon: "Our security depends on ensuring that Iran does not become nuclear." He added that the Trump administration "made it much harder for the next president to achieve that goal by gutting the Iran nuclear deal."
Klobuchar said she would try to prevent Iran from becoming a nuclear power by starting negotiations again.
"Because of the actions of Donald Trump, we are in a situation where ... Iran is starting to enrich uranium again, in violation of the original agreement. So what I would do is negotiate," Klobuchar said.
CNN moderator Wolf Blitzer asked Warren how she would deal with the fact that a third of her supporters say her ability to lead the military is more of a weakness than a strength, according to a new CNN/Des Moines Register poll. She noted her work on the Senate Armed Services Committee and her visits to troops around the world.
"I fight for our troops, to make sure they get their pay and the housing and medical benefits that they've been promised, that they don't get cheated by giant financial institutions," she said, noting that she has three brothers who served in the military.
Candidates clash over the ambition of their plans
The candidates engaged in a now familiar debate over the varying costs of their health care programs, particularly the "Medicare for All" plan embraced by Sanders and Warren. Klobuchar, who supports building on the Affordable Care Act, called Medicare for All a "pipe dream."
Sanders insisted his campaign proposals would not bankrupt the country even though it would double federal spending over the next decade and insisted that his transition fund would ease the pain of likely job losses in towns like Des Moines where the insurance is central to the economy.
Warren challenged Buttigieg on his plan to make Medicare for All an option.
"The numbers that the mayor is offering don't add up," she said.
Buttigieg, in response, rejected the notion that his plan was too small.
"We have to move past Washington mentality that suggests that the bigness of plans only consists of how many trillions of dollars they put through the Treasury," he said.
Buttigieg and Klobuchar also raised their objections to Warren's and Sanders' respective plans providing free college for everyone. Klobuchar argued that the money would be better directed to job training for the professions that will face shortages in the future, like home health care, nursing assistants and electricians.
Buttigieg argued that there's a "very real choice about what we do with every single taxpayer dollar that we raise" and said those dollars should be used "to support everybody -- whether you go to college or not."
"We have to target the tax dollars where they will make the biggest difference," Buttigieg said. "I don't think subsidizing children of millionaires to pay zero in tuition of public college is the best use of the scarce taxpayer dollars."
Businessman Tom Steyer was asked -- as a billionaire -- whether he would have supported free college for his children.
"No," Steyer answered simply, noting that he has supported a wealth tax for more than a year. "I believe that the income inequality in this country is unbearable and unjust and unsupportable. The redistribution of wealth to the richest Americans from everyone else has to end."
This is a breaking story and will be updated.