Carl Forti, a founder of Restore Our Future and its spokesman, predicted that as many as 20 Republican-leaning super PACs would seek to oust Obama and would work together to figure out how to gain maximum traction from their ads.
"The outside groups are at our best when we do coordinate," said Forti, who was the political director for Romney's failed 2008 presidential bid and has been a Crossroads strategist since 2010. "We did so in the 2010 cycle and I expect and hope we will be able to coordinate again."
At least one super PAC backing Obama's re-election has been on the air attacking Romney.
Priorities USA Action, founded by two former Obama White House aides, went up with a new ad this week in Florida, Iowa, Ohio and Virginia depicting Romney as a heartless businessman who would cut benefits for the middle class to give tax cuts to the wealthy as president.
"Mitt Romney. If he wins, we lose," the ad says.
Still, Priorities is spending just under $700,000 on the current ad buy, reflecting the group's significant fundraising disadvantage compared to Republican-leaning groups. Priorities and its affiliated nonprofit group have raised just $10 million since last year, while American Crossroads and Crossroads GPS together have raised more than $100 million since 2010.
Priorities founder Bill Burton insists the group's fundraising has picked up and will provide a counterbalance to Republican super PAC ads.
"People are starting to see the right-wing money machine is raising a ton of money. President Obama's re-election is in doubt. People are really starting to turn in a way they hadn't before," Burton said.
The presidential campaigns and most super PACs have a midnight Friday deadline to disclose their March fundraising totals.
It's unclear whether other pro-Obama groups will run ads supporting his re-election. While labor unions have run ads supporting Obama and other Democratic candidates in past elections, AFL-CIO political spokesman Jeff Hauser said the labor federation planned to devote its resources to field organizing rather than television.
Associated Press writer Jack Gillum in Washington contributed to this report.
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