Just three days before the crucial Nevada caucuses, Democratic candidates took the stage in a contentious debate, firing off rounds of attacks on newcomer Mike Bloomberg. Former Vice President Joe Biden, Sen. Bernie Sanders of Vermont, Sen. Elizabeth Warren of Massachusetts and Sen. Amy Klobuchar of Minnesota, former South Bend Mayor Pete Buttigieg and former New York Mayor Bloomberg spent two hours Wednesday night duking it out at the Paris Las Vegas Hotel & Casino. It was the ninth overall debate – and the most pugnacious. But it was the first that featured Bloomberg, who doesn't take campaign contributions and did not qualify for previous ones because he didn't meet donor thresholds. The debate opened with Warren and Sanders, who have built their campaigns around the promise to reduce wealth inequality, throwing jabs at Bloomberg, who has spent about $400 million of his personal fortune on campaign ads. since joining the race in late November. Despite his presence at the Nevada debate, Bloomberg is not on a ballot until Super Tuesday March 3. Sanders maintains a lead in national polls and held a 19-point edge in Nevada, according to a survey released Monday. The Nevada caucuses could present an opportunity for Biden, who maintained the lead for months, to bounce back against Sanders.

However, Biden, the former front-runner, came across as mostly an afterthought in Wednesday's debate. He is at risk of underperforming in Nevada on Saturday and the South Carolina primary on Feb. 29, after he flopped in Iowa and New Hampshire. Here are the night's top moments:

Bloomberg takes an immediate beating

Democratic presidential hopeful Vermont Senator Bernie Sanders speaks during the ninth Democratic primary debate of the 2020 presidential campaign season co-hosted by NBC News, MSNBC, Noticias Telemundo and The Nevada Independent at the Paris Theater in Las Vegas, Nevada, on February 19, 2020. Mark Ralston | AFP | Getty Images

Bloomberg took a beating from his rivals on Wednesday at the very start. The harshest attack came from Warren, who said Bloomberg was a "billionaire who calls women 'fat broads' and 'horse-faced lesbians.'" "And no, I'm not talking about Donald Trump, I'm talking about Mayor Bloomberg," Warren said, prompting gasps from the audience. Sanders also went after Bloomberg, saying the stop-and-frisk policing policy that Bloomberg oversaw as mayor "went after African American and Latino people in an outrageous way. That is not a way you are going to grow voter turnout." Bloomberg responded that Sanders' proposed "Medicare for All" health-care overhaul was no way to build a broad coalition. "You don't start out by saying I've got 160 million people, I'm going to start taking away the insurance policy they love," he said. "If he goes and is the candidate, we will have Donald Trump for another four years, and we can't stand that."

Buttigieg targets Sanders and Bloomberg

The former South Bend mayor lumped together Sanders and Bloomberg, calling them "the two most polarizing figures on this stage." "Most Americans don't see where they fit if they've got to choose between a socialist who thinks capitalism is the root of all evil and a billionaire who thinks money ought to be the root of all power," he said. "Let's put forward somebody who's actually a Democrat," he added, positioning himself as the moderate between the two. Bloomberg is a former Republican and Sanders is registered as an independent. "We shouldn't have to choose between one candidate who wants to burn this party down and another candidate who wants to buy this party out," he said. Sanders returned fire, accusing Buttigieg of taking contributions from billionaires like Bloomberg, who has a net worth of about $60 billion. "What we are saying, Pete, is maybe it's time for the working class of this country to have a little bit of power rather than your billionaire campaign contributors," he said. Bloomberg did not respond to Buttigieg on stage.

Warren tears into Bloomberg on harassment

Warren unleashed another attack on Bloomberg, pressing him to release women employees from nondisclosure agreements that prevent them from discussing sexual harassment and gender-based discrimination in the workplace. Bloomberg fumbled on a defense of his reported lewd comments toward female employees, using the opportunity to call attention to the women who work for him in high-ranking positions. Warren chimed in immediately after his response. "I hope you heard what his defense was: 'I've been nice to some women.' That just doesn't cut it," she said, drawing gasps from the audience. "He has gotten some number of women — dozens, who knows — to sign nondisclosure agreements both for sexual harassment and for gender discrimination in the workplace. So Mr. Mayor, are you wiling to release all of those women from those nondisclosure agreements so we can hear their side of the story?" Bloomberg responded, saying, "We have a very few nondisclosure agreements." "How many is that?" Warren interjected. "Let me finish. None of them accused me of doing anything other than — maybe they didn't like a joke I told," Bloomberg said, causing the audience to groan.

Bloomberg botches tax-return question

Bloomberg stumbled in response to a question about when he planned to release his tax returns. "It just takes us a long time," Bloomberg said, drawing boos from the audience. "Unfortunately, or fortunately, I make a lot of money and we do business all around the world, and we are preparing it. The number of pages will probably be thousands of pages. I can't go to TurboTax." "But I put out my tax return every year for 12 years in City Hall. We will put out this one — it tells everybody everything they need to know about every investment that I make and where the money goes and the biggest item is all the money I give away." Bloomberg is the wealthiest candidate in modern times to mount a viable campaign for president, and has so far spent more than $400 million on ads, despite not appearing in the first four voting contests. In 2016, Trump was the first major party candidate in nearly 50 years not to release tax returns to the public.

Bloomberg slams Sanders for being a rich socialist