Story highlights "We need your contribution by 11:59 P.M. Tonight," the email said

"Crooked Hillary is about to invade your TV with ads attacking Mr. Trump," Team Trump said

Washington (CNN) The Donald Trump campaign on Saturday released its first "emergency" fund-raising email, in response to an ad blitz from the Hillary Clinton campaign.

"Right now we're facing an emergency goal of $100,000 to help get our ads on the air. We need your contribution by 11:59 P.M. Tonight," the email from Team Trump said.

"Crooked Hillary is about to invade your TV with ads attacking Mr. Trump. But we're preparing to fight back," it reads.

The email promises to release ads attacking Clinton on her role in Benghazi, the integrity of her donors and reported FBI probing of her private email server while secretary of state.

The urgent fundraising email is routine for most presidential campaigns. But it's particularly notable since Trump insisted repeatedly during the GOP primary season that he was self-funding his campaign, only to start asking for donations later on.

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