President Obama's campaign warned supporters that the president could lose his reelection bid in an attempt to convince donors to contribute more money.

"We are not guaranteed to win this election," Ann Marie Habershaw, chief operating officer for the campaign, wrote in the fundraising email. "If there's anyone still out there acting like we have this thing in the bag, do me a favor and tell them they're dead wrong." Habershaw warned that Romney, who outraised Obama in May, would continue to build a warchest now that he is the Republican nominee.

The urgent message is the latest in a series of increasingly-dire fundraising efforts."If the general election were held today, President Obama would lose to Mitt Romney," campaign manager Jim Messina wrote supporters in March.  Yesterday, Messina announced that "we got beat" in another message built around Romney's May edge in fundraising.