Sen. Elizabeth Warren (D-Mass.) opened the Democratic debate in Las Vegas, Nevada, with a blistering attack on New York billionaire Mike Bloomberg.

"I'd like to talk about who we're running against," said Warren.

"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!" she added.

"Democrats are not going to win if we have a nominee who has a history of hiding his tax returns, of harassing women, and of supporting racist policies like red-lining and stop and frisk," she continued.

"Look, I'll support whoever the Democratic nominee is, but understand this, Democrats take a huge risk if we just substitute one arrogant billionaire for another," she concluded. "This country has worked for the rich for a long time and left everyone else in the dirt."

Bloomberg responded by reciting items from his resume and claiming he has the best chance to beat President Donald Trump.

"I'm a New Yorker, I know how to take on an arrogant con man like Donald Trump who comes from New York," said Bloomberg.

"I'm a mayor, or I was a mayor. I know how to run a complicated city, the biggest, more diverse city in this country," he added.

Here's the video of her attack: