Michael Bloomberg had a huge target on his back even before he walked onto the stage in Wednesday night’s Las Vegas debate. And less than 10 minutes into the nationally televised debate, the former New York City mayor knew he was in a fight.

I'd like to talk about who we're running against. 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.

— U.S. Sen. Elizabeth Warren

U.S. Sen. Bernie Sanders immediately attacked Bloomberg’s stop-and-frisk policy while the Big Apple’s mayor.

In order to beat Donald Trump we are going to need the largest voter turnout in the history of our country. Mr. Bloomberg's record of stop-and-frisk is not going to do that.

Bloomberg fired back at Sanders, who is leading the race by consistently larger polling margins, by saying Sanders will kick millions of Americans off of their healthcare.

The two most polarizing figures on this stage ... 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.

— Former South Bend, Ind., Mayor Pete Buttigieg

Bloomberg was also attacked by Warren over allegations of inappropriate sexist remarks.

Mr. Mayor, are you willing to release all of those women from those nondisclosure agreements, so we can hear their side of the story?

— Warren

We have very few nondisclosure agreements. Maybe they didn't like a joke I told.

— Bloomberg

Biden, who was vice president for eight years under President Barack Obama, attacked Bloomberg before the debate.

Biden was criticizing Bloomberg’s record of citing Obama’s alleged support of his campaign. Foreshadowing the fight ahead, Bloomberg fired back.

Bloomberg’s campaign tweeted a video of Biden complimenting Bloomberg in the past as Big Apple’s mayor, and as a businessman.

“I don’t know anybody I’ve worked with in my career ... who does more to create the future than you, Mike,” Biden says in the video.

Social media watchers were almost unanimous in their opinion that Bloomberg made a poor showing in his first debate.

Social media watchers noticed Biden’s loud, almost-to-the-point-of-shouted, responses.

But Bloomberg wasn’t the only candidate under attack Wednesday night. Warren took aim at Klobuchar’s health care plan which, the Massachusetts senator said, was "like a Post-It note: 'Insert plan here.'"

I must say I take personal offense, since Post-It notes were invented in my state.

— Klobuchar

The attacks underscore how seriously Democrats are taking Bloomberg’s campaign, now that he’s rocketed to double-digit support in national polls and qualified to appear in debates. He was a lifelong Democrat before winning the New York mayor’s race as a Republican in 2002. He later switched to independent and formally registered as a Democrat last year.

»MORE: Bloomberg qualifies in the nick of time for Las Vegas debate

Bloomberg has spent more than $400 million on advertising and has risen in national polling as a result. That has allowed him a place on the debate stage in Las Vegas, after the Democratic National Committee dropped an additional requirement of reaching a certain number of donors. Since Bloomberg accepts no donations, polls were the only way he could qualify.

A new NPR/PBS NewsHour/Marist poll published Tuesday shows Bloomberg with 19% support nationally in the Democratic nominating contest.

At the same time Democrats were debating, President Donald Trump was holding a rally in Phoenix which was attended by thousands of the incumbent chief executive’s supporters.

Early voting began last week the weekend for Saturday’s Feb. 22 Nevada Democratic Caucus. Democrats are vowing not to repeat the debacle that was the Iowa caucus, the Democrats’ first big political event of 2020 that turned into a circus of delays, glitches and fodder for President Trump and Republicans.

»Never again: Nevada Democrats vow not to repeat Iowa’s missteps

After Saturday’s caucus comes the Feb. 29 South Carolina primary, in which Biden is pinning his hopes after poor showings in Iowa and New Hampshire.

»2020’s important election dates you should know

Then comes Super Tuesday on March 3, in which 14 states and American Samoa will cast their primary ballots.