According to an analysis by ABC News, about half the money given during the first six months of this year to Restore Our Future, a PAC set up to support Romney, came from donors who also gave the federal maximum of $2,500 to his campaign.
And the vast majority of the money flowing into the coffers of Priorities USA Action, a PAC whose goal is to help Obama get re-elected, was given by contributors who also gave the maximum to the Obama campaign directly.
Restore our Future and Priorities USA Action are technically independent entities, but their founders' make no secret that their mission is to help Romney and Obama win in 2012.
Both groups are so-called super PACs that can accept unlimited donations. They were set up by former Romney and Obama advisers and can spend money in support of both candidates, though they are not allowed to directly coordinate with the campaigns.
But the net effect is that they allow donors who support Romney and Obama -- but are limited to $2,500 in direct campaign donations -- to back the front runner for the Republican nomination and the incumbent president with unlimited resources.
Of the $12.2 million raised in the first six months of the year by Romney's allies in Restore Our Future, more than $6 million was given by Romney campaign donors. Of the 90 donations to the PAC, approximately 57 came from Romney donors (in some cases it is difficult to ascertain from the FEC report if identical names represent the same person.)
Take Paul Edgerly. He works at Romney's former company, Bain Capital, and donated the legal maximum $2,500 to Romney's official campaign. He also gave $500,000 to the PAC. His wife Sandra did exactly the same thing.
Marriott hotel heirs JW Marriott Jr. and Richard Marriot each gave $500,000 to the PAC on top of their donations to the campaign. (Note: Willard Mitt Romney is named after the "W" in the original J.W. Marriott.)
James Davis, CEO of New Balance Sneakers, gave another $500,000. And the co-CEO's of Sun Capital, Rodger Krouse and Marc Leder, each threw in an additional $125,000.
Representatives for Restore Our Future declined to comment.
Not everyone is double donating. John Paulson, the hedge fund investor who famously made billions by betting on the housing bubble to burst, gave $1 million to the PAC, but nothing to the Romney campaign.
For the wealthy who want to support the former Massachusetts governor who is topping most national GOP 2012 primary polls, the sky is the limit.
In the deep-pocketed pool of Obama supporters, the pattern of giving looks much the same. Eight of the 24 individual donors to the group Priorities USA Action -- founded by former White House staffers Bill Burton and Sean Sweeney -- donated to Obama's re-election campaign fund.
In fact, four of those eight wealthy contributors, who gave the legal maximum to Obama for 2012, also turned to Priorities USA to give an additional $2.6 million combined. That total represents 82 percent of all the money the group has raised this year, and will likely be spent primarily in support of Obama's re-election.
Dreamworks CEO Jeffrey Katzenberg is Priorities USA Action's biggest donor, giving $2 million. He is also one the Obama campaign's top financiers, bundling more than $500,000 in additional donations from his friends and colleagues.
The elite Beverly Hills couple J.J. Abrams, a star producer and director, and his wife, Katie McGrath, a public relations executive, both gave the legal limit to the president and an additional $50,000 each to Priorities USA. Abrams hosted an entertainment industry panel discussion with first lady Michelle Obama for her Joining Forces initiative in Hollywood in June.
Fred Eychaner, a Chicago-based media executive who gave $500,000 to Priorities USA, has also been a loyal supporter of the Obama campaign as a donor and bundler. Obama appointed Eychaner to be a trustee of the Kennedy Center for the Performing Arts in 2010.
Asked whether the donors' behavior violates the spirit of campaign finance laws, Burton suggested the arrangement is necessary – for right or for wrong – given the influence of conservatives' money in politics.
"Given the hundreds of millions of dollars pledged by Karl Rove and the Koch brothers to defeat President Obama and progressive values, we thought the best course of action was to fight back," Burton told ABC News by email.
He was referring to the largest of the "super PACs" American Crossroads, which was co-founded by Rove.
"The Supreme Court changed the campaign finance rules and while we may not like them, we're not going to allow the candidates and values we care about to be overrun with right wing money," he said.
But many nonpartisan campaign finance watchdogs say groups like Restore Our Future and Priorities USA, while acting in accordance with the law, are perverting the democratic system.
"We have long had a national policy of establishing limits on what the individual can give to the political candidate because of even the appearance of corruption," said Ellen Miller, co-founder and executive director of the Sunlight Foundation, a nonpartisan campaign finance watchdog. "Now we have no limits in effect."
Miller said the concept of individuals making multiple political contributions in the interest of a candidate or cause is not new. But, she called the rise of super PACs run by the "friends" of the candidates particularly "frightening."
"Under the law, the candidates and the PACs are not supposed to coordinate. But it's a classic Washington wink and a nod," she said.
ABC News' Michael Falcone contributed to this report