Fearing a tide of spending by outside conservative groups, President Obama is giving his blessing to a pro-Democratic Party “super PAC” that will work to help his reelection, his campaign said late Monday.

Obama campaign manager Jim Messina said in a message to supporters that “our campaign has to face the reality of the law as it stands,” which he said gives a large financial advantage to Republicans and their allied groups. Messina said Obama will throw his support to Priorities USA Action, a super PAC founded by two former White House aides that until now has been unable to match its conservative competitors in fundraising.

“We can’t allow for two sets of rules in this election whereby the Republican nominee is the beneficiary of unlimited spending and Democrats unilaterally disarm,” Messina wrote.

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The move marks a clear political risk for Obama, who has staked much of his political career on opposition to the outsized role of “secret billionaires” and other monied interests while also attempting to win reelection in a struggling economy.

The decision underscores the dramatic changes that have rocked the U.S. political system in the wake of a series of rulings, including Citizens United v. Federal Election Commission, that have made it easier for corporations, unions and wealthy individuals to bankroll political advertising and other efforts. The clearest example of the changes have been super PACs, which can raise and spend unlimited funds as long as they do not directly coordinate with candidates, who nonetheless can help raise limited amounts of money for them.

Priorities USA raised just $6.7 million in 2011 between its super PAC and related nonprofits, officials have said. That sluggish pace put it far behind its Republican rivals, in part because many major Democratic donors said they did not feel the Obama campaign was supportive of the effort.

Obama has regularly slammed the Citizens United decision as misguided, and complained about super PACs in an interview aired earlier Monday on NBC News. “Unfortunately right now, partly because of Supreme Court rulings and a bunch of decisions out there, it is very hard to get your message out without having some resources,” he said.

Jonathan Collegio, spokesman for American Crossroads, one of the largest Republican-leaning groups, called the shift a “brazenly cynical move by Barack Obama and his political handlers, who just a year ago had the chutzpah to call outside groups a threat to democracy.”

Messina said senior Obama campaign officials as well as some White House and Cabinet officials will attend and speak at Priorities USA fundraising events, but will not solicit donations during the appearances. Obama, first lady Michelle Obama and Vice President Joe Biden will not appear at any Priorities USA events, he said.

Super PACs have outpaced regular campaigns in the GOP primary race, including one group supporting Newt Gingrich fueled by $11 million from casino magnate Shel Adelson and his family. Many other outside nonprofit groups are also able to spend unlimited funds on elections without having to reveal their donors.