NYT reports:

This campaign is the first time the group has expressly advocated for Mr. Obama’s defeat in an ad. “We don’t take this lightly,” said Tim Phillips, president of Americans for Prosperity. “We’ve always stayed away from express advocacy. But given the president’s disastrous record, we felt this was necessary.”

Subsequent ads in this campaign will feature the personal stories of Americans who have been hit hard by the economic collapse, Mr. Phillips added.

Campaign finance experts noted that by taking direct aim at the president in their ads, Americans for Prosperity was taking advantage of a legal loophole that allows it to keep the identities of its donors secret.

“If the organization had continued running ads attacking Obama without containing express advocacy they would have had to disclose all their donors dating back to the beginning of 2011,” said Fred Wertheimer, president of Democracy 21, which fights for greater campaign finance transparency.