A guide to the super PACs backing 2012 presidential hopefuls

Over the next few days, President Obama and his Republican challengers are set to file reports disclosing how much they raised for their campaigns between July and September and where that money came from.

But for some of the candidates, the reports offer only a glimpse of the cash being spent on their presidential efforts.

In a development that could seriously shift the financial dynamics of the 2012 campaign, Obama, Rick Perry, Michele Bachmann, Mitt Romney and Ron Paul all have at least one so-called "super PAC" raising and spending unlimited amounts of cash to support their White House bids.

Campaign laws block outside groups from directly coordinating with the candidates and their campaigns (at least for now), but many of the groups are being run by close supporters and, in some cases, former staffers of the individual candidates. In other words, many of the groups are already familiar with a particular candidate's strategy and can adjust their own plans without having to deal directly with the actual campaigns.

Some of the super PACs could very likely raise and spend more cash than the candidates they are supporting—a financial status that could dramatically impact the direction of the 2012 Republican primary and ultimately the general election campaign.

Here's a quick guide to the assembled super PACs so far and which candidates they are supporting:

Restore our Future (Mitt Romney) Formed last fall by several former Romney aides, the committee has raised more than $12 million to boost the former Massachusetts governor's 2012 bid—including four contributions of $1 million apiece. One of those contributions came from a former Romney co-worker at Bain Capital, who initially gave his donation through a mysterious limited liability company to hide his identity. While Romney can't legally coordinate with the group, he has appeared at fundraisers sponsored by the PAC.

Priorities USA (Barack Obama) Formed by former White House aides Bill Burton and Sean Sweeney, the group raised $3.2 million between May and June to support Obama's campaign. That includes a single $2 million contribution from producer Jeffrey Katzenberg, who also happens to be a top bundler to Obama's re-election campaign. While PUA files a financial report with the Federal Election Commission, the committee has a sister 501(c)4 group—Priorities USA Action—that can raise and spend unlimited amounts of cash without disclosure.

Make Us Great Again (Rick Perry) Headed up by Perry's former chief of staff, Mike Toomey, this group was formed in July—just weeks before the Texas governor officially joined the race. Americans for Rick Perry, another super PAC that had been raising cash to support Perry, dropped its efforts to unite behind MUGA, which has said it plans to raise at least $55 million to support Perry's bid.

Citizens for a Greater America (Rick Perry) Formed last month by Perry allies, this 501(c)4 group won't publicly disclose its spending or donors, allowing contributors to support Perry's bid anonymously.

Revolution PAC (Ron Paul) This committee was launched in July by a group of longtime Paul supporters and staffers--including Penny Langford, the Texas congressman's former political director, and Joe Becker, who was counsel to Paul's 2008 presidential campaign. The super PAC has already been active in the campaign, running ads targeting Rick Perry and Mitt Romney, and it helped boost Paul's efforts at the Iowa straw poll, where he narrowly lost to Bachmann.

Keep Conservatives United (Michele Bachmann) Bob Harris, a North Carolina political operative, launched this group to advocate Bachmann's 2012 bid in mid-August. In recent weeks, the committee has trashed Rick Santorum and Herman Cain for not being true conservatives and has run ads trashing Rick Perry's record on spending and his push to inoculate young girls against HPV in Texas.

Citizens for a Working America (Michele Bachmann) Initially formed to boost conservative candidates in the last weeks of the 2010 campaign, this committee announced in August it would focus its efforts solely on Bachmann's 2012 bid. The group is being steered by former Ohio Secretary of State Ken Blackwell, a rock star in the conservative movement, and Ed Brookover, a longtime political adviser to Bachmann. But it's unclear what the group has been doing, beyond raising cash. It has yet to launch any ads, and its website now appears to be off line.

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