NEW YORK — Super PACs, which can raise and spend unlimited campaign money, have jumped into the presidential contest with an unmistakable message: Game on.
A super PAC supporting Mitt Romney is unleashing a brutal attack ad on Newt Gingrich. Another has been running ads for weeks for Rick Perry. Spending by yet another super PAC in New Hampshire may be the only thing keeping Jon Huntsman's struggling campaign afloat.
Nearly two years after the Supreme Court eased restrictions on corporate money in political campaigns, super PACs have become a major force in the presidential contest. They can attack or support individual candidates as long as they don't coordinate directly with the campaigns themselves.
Conservative-leaning groups spent millions to help Republicans wrest control of the House and pick up several Senate seats in 2010. The 2012 campaign is the first to test the groups' influence on presidential politics.
Anthony Corrado, a professor of government at Colby College who studies campaign finance, said super PACs are likely to outspend the candidates themselves in the early contests.
"They have substantial amounts of money, they can raise money quickly, and they have every incentive to spend it in the early states," Corrado said. "For a super PAC supporting a particular candidate, now is the time to spend money. It doesn't do any good to wait until April."
Restore Our Future, a super PAC supporting Romney, the former Massachusetts governor, is set to start running a harsh attack on Gingrich as part of an enormous, $3.1 million advertising buy in Iowa less than four weeks before the state's kickoff caucuses. The 60-second ad says Gingrich's "baggage," including $1.6 million he took in fees from housing giant Freddie Mac before the 2008 mortgage meltdown, would make him an easy target for President Barack Obama in the general election.
Make Us Great Again, which backs Perry, has spent more than $2 million on ads over several weeks in Iowa, supplementing the campaign's own substantial advertising buy there. The group has also run ads supporting Perry in South Carolina.
The pro-Perry spending hasn't helped the Texas governor much. He still lags badly in Iowa, trailing Romney, former House Speaker Newt Gingrich and Texas Rep. Ron Paul in recent polls.
The pro-Huntsman Our Destiny PAC has spent about $1.3 million in New Hampshire. They've been the only TV ads airing that support the former Utah governor, whose cash-strapped campaign has lacked the money to run its own ads.
The pro-Romney PAC started soft.
Restore Our Future's first ad, which debuted Thursday, goes after Obama while stressing Romney's background as a governor and successful businessman. But the new, negative ad aims to slow Gingrich's surging momentum in Iowa and elsewhere.
Romney may welcome such help. His campaign has begun to go after Gingrich after spending months trying to focus its attacks on Obama.
Several members of Congress supporting Romney have come forward to criticize Gingrich as self-serving and undisciplined, but none of those accusations has shown up in paid advertising yet.
A pro-Gingrich super PAC, Solutions 2012, is promising to step into the campaign soon. The group's treasurer, Colorado-based Republican strategist Charlie Smith, said it will assist Gingrich in Iowa with get-out-the-vote efforts and possibly some television but has yet to reserve any advertising time. Smith declined to say how much money the group has raised.
Gingrich has tried to avoid attacking Romney or any of his other Republican rivals, a strategy that has been credited in part for his strong polling numbers and a spike in fundraising. His first campaign ad, which went on the air in Iowa this week, offered a gauzy, positive message.
Smith said Solutions 2012 could potentially launch negative attacks on the other candidates if necessary.
"Newt has been focusing on being positive and, if possible, we want to stay positive," Smith said.
Other super PACs have also started to make their mark on the presidential contest.
Priorities USA Action, which supports Obama's re-election bid, launched an ad on Iowa cable stations Thursday advocating a tax increase for millionaires. The group, headed by two former Obama White House aides, has spent $148,000 since early November, mostly on Web and TV ads bashing Romney.
Crossroads GPS, by far the largest and most influential super PAC during the 2010 midterm elections, has said it would get involved in the presidential race during the general election. But the group has spent $300,000 in Iowa targeting Democratic Rep. Leonard Boswell for supporting Obama's health care overhaul, making the group's criticism of the president part of the political conversation in the weeks leading up to the caucuses.
Crossroads is expected to further ramp up its attacks on Obama's record in coming weeks.
Associated Press writer Jack Gillum in Washington contributed to this report.
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