Democrat Hillary Clinton didn't need to win the second presidential debate. But it was a do-or-die moment for Donald Trump, and he tried to rattle, taunt and unnerve his opponent.

Trailing in the polls and abandoned by droves of his party’s leaders, the two started the debate by refusing to shake each others' hands and Trump interrupted Clinton throughout the debate, prompting exasperated moderators to repeatedly ask him to quiet down.

He summoned her speech calling half of Trump’s supporters “deplorables,” painting her as a cynical and jaded politician who has lost sight in the American public. “She’s got tremendous hatred,” he said at one point.

He threatened to sic his Attorney General on Clinton to delve into her use of a personal email server while she was secretary of state if he wins election, saying “you should be ashamed of yourself.”

And he revived allegations of sexual misconduct by her husband, Bill Clinton, by inviting four of his alleged victims to the debate.

“If you look at Bill Clinton – far worse,” said Trump. “Mine were words, his were action.”

The sharpest in a series of gutty exchanges came after Clinton said "it’s just awfully good that someone with the temperament of Donald Trump is not in charge of the law in our country."

He shot back: "Because you'd be in jail."

Clinton didn’t have the same strong performance she had in her first debate at Hofstra University, but she took away two minor victories that could come back to haunt her opponent.

She watched as Trump admitted to openly disagreeing with Mike Pence, his running-mate, on how to end the civil war in Syria. He said the U.S. should focus on eliminating the Islamic State terror group, while Pence has called for “American strength” to counter Russia’s role in the civil war.

And Donald Trump said “of course” he used a $916 million loss in 1995 to avoid paying federal income taxes. “I understand the tax code better than anybody that’s ever run for president,” Trump said, adding: “It’s extremely complex.”

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