The first viral moment of the ninth Democratic debate came less than five minutes into the event and was courtesy of U.S. Sen. Elizabeth Warren.

“I'd like to talk about who we're running against, a billionaire who calls women ‘fat broads’ and ‘horse-faced lesbians,” she said. “And, no, I'm not talking about Donald Trump. I'm talking about Mayor Bloomberg.”

Her comment, which referenced allegations of sexual harassment that former New York City Mayor Michael Bloomberg faced, may have been among the night’s most caustic. But it was indicative of the debate overall: candidates taking jabs at each other but especially Bloomberg, who was participating in a debate for the first time.

The six Democrats on stage Wednesday night battled nearly the entire two hours. At several points, the debate unraveled into cross-talk even as the moderators tried to retain control.

Former South Bend, Ind., Mayor Pete Buttigieg and U.S. Sen. Amy Klobuchar of Minnesota sniped at each other repeatedly.

Buttigieg accused Klobuchar of being unprepared to lead, saying her inability to name the Mexican president on demand was indicative that she was not ready for the job.

Klobuchar fought back, accusing Buttigieg of taking cheap shots because he doesn’t understand governing on a larger scale.

U.S. Sen. Bernie Sanders of Vermont responded to critiques of his Medicare for All health plan, and he denounce his supporters who have made abusive posts online in defense of his campaign. His opponents said that Sanders’ brand of democratic socialism would be easily defeated by President Donald Trump in a general election.

“I don't think there's any chance of the senator beating President Trump,” Bloomberg said of Sanders. “You don't start out by saying I've got 160 million people I'm going to take away the insurance plan that they love.”

Former Vice President Joe Biden, when he could get a word in, attempted to position himself as the candidate with the most experience and best positioned to beat Trump.

But it was Warren who seemed to have arrived with the most energy to punch back at her opponents. She accused Klobuchar and Buttigieg of having thin healthcare proposals: his was a “powerpoint” and hers was a “post-it note.”

Later, she called on Bloomberg to release anyone who has accused him of harassment from non-disclosure agreements that prevent them from speaking out.

“Understand, this is not just a question of the mayor's character,” she said. “This is also a question about electability. We are not going to beat Donald Trump with a man who has who knows how many nondisclosure agreements and the drip, drip, drip of stories of women saying they have been harassed and discriminated against.”

Bloomberg refused to void the agreements and said some of the accusations against him were filed by women who didn’t like jokes he told.

He also stopped short of apologizing outright for continuing the controversial “stop and frisk” policing policy that unfairly targeted people of color, saying that crime-fighting initiatives were needed but it went too far.

The night ended on the question of what could happen if none of the candidates obtains a majority of delegates ahead of the Democratic National Convention this summer.

Five of the people on stage all said that DNC rules are in place to guide next steps if that becomes the case. Sanders, who is the most likely at this point to fall in the position of having the highest number of delegates but not enough to claim the nomination, was predictably the only one to support bending the rules.

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