LAS VEGAS – Former New York Mayor Mike Bloomberg took a beating from his rivals on Wednesday from the very start of his first appearance on a Democratic debate stage.

All of the five Democrats standing beside him jumped on their first opportunity to go after the billionaire, who has been dropping hundreds of millions of dollars on advertisements fueling his presidential bid in recent months.

The jabs, which had been telegraphed for days, zeroed in on Bloomberg's record on race as mayor of New York, as well as alleged instances of sexual harassment against employees of his flagship business Bloomberg LP.

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The harshest attacks came from Sen. Elizabeth Warren of Massachusetts, who said that 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.

Warren, who has been declining in recent national and state polls, said that Democrats will not win "if we have a nominee who has a history of hiding his tax returns, of harassing women, and of supporting racist policies like redlining and stop-and-frisk."

"Democrats take a huge risk if we just substitute one arrogant billionaire for another," Warren said. Warren noted that she will support whoever is the nominee.