Updated

"If [then-Obama communications director] Robert Gibbs started running a [independent political expenditure group] and I called Robert Gibbs and said, 'Stop running ads on my behalf,' are you suggesting I would have no influence over Robert Gibbs?"

-- Then Sen. Barack Obama, as quoted by Politico, in West Des Moines, Iowa in December of 2007 attacking opponent John Edwards for negative ads being run by an outside group run by a former Edwards aide.

President Obama is now starting to pay the price for his intensely negative, very personal campaign against soon-to-be Republican nominee Mitt Romney.

On Monday, Power Play predicted that the intense personal animus that Obama had for Romney as described in a forthcoming Politico book could cause serious trouble for Obama's campaign. The danger when the man or woman at the top really despises his opponent is that underlings will go too far in their attacks.

On Tuesday, the Obama-backed political action committee unleashed the nastiest ad of the presidential contest so far. The group, Priorities USA, is led by a former top Obama aide, has the president's blessing and has received fundraising help from top Obama deputies, including his campaign manager.

More On This...

The new ad stars a steelworker from Obama's first attack ad of the general election, which accused Romney of being a "vampire" because of the shuttering of a steel mill in Kansas City. The PAC ad picks up the story of the steelworker after the closure and lays the blame at Romney's feet for his wife's death from cancer five years later because their health insurance had been disrupted.

The Obama-backed group can't coordinate with the campaign, but it can use the campaign's work. In this case, the campaign had already known about the cancer story since the steelworker, Joe Soptic, had already told the tale on a conference call with reporters when the Obama ad first ran back in May.

Obama's campaign knew that its opening attack on Romney would be heavily scrutinized. The highly negative and personal nature of Obama's campaign has raised eyebrows even among the most docile members of the media. The campaign also knew that the ad tugged at the truth a bit. Romney had left the firm when the plant closed, the intervention had preserved many jobs for several years, etc.

But they could walk that line and survive, given the low standards for veracity in campaign ads. Accusing Romney, with several more leaps in logic, of killing a man's wife, though, was too much for the campaign of a sitting president, even one that has decided to be nasty.

But for what is now called a "super PAC," groups that Obama once called "shadowy" but subsequently embraced in his bid to win a second term, perhaps the consequences would not be so bad.

The Obama-backed Obama backers at Priorities USA thought they were doing a favor for the president: going where he couldn't go. And given what Obama has said about Romney and the months of character attacks on the Republican, they certainly had every reason to think that the president would be pleased that they had found an even uglier way to go after Romney.

Henry II asked, "Will no one rid me of the pestilent priest?" and some enterprising knights offed Thomas Becket. Obama's campaign called Romney a possible felon and a vampire, and his former aides decided to go all the way and call him a murderer.

The Obama-backed group picked up the cancer story and ran with it. Using the campaign's legwork, Priorities USA put together an ad so nasty and so tendentious that even Democrats feel obliged to disown it.

The standard defense in politics when someone does something bad on your behalf is to, at least at first, deny knowledge or involvement and then throw your hands up at the way the political system works.

Obama surrogates tried that on Wednesday, saying they had no knowledge of the story and washed their hands of the ad. And in true political PR fashion, made the pivot to say that while they didn't know anything about the ad, it was true that Romney didn't care about workers having health insurance.

But the campaign did know the story, because they had told it first, just not through a television bullhorn.

The Pontius Pilate defense did not work because Priorities USA had so carefully hewed to the original Obama attack -- the same steelworker, the same story -- that there was no plausible deniability.

Now, Obama finds himself with his campaign having been caught feigning ignorance about an unsavory ad produced by an organization he supports. For a sitting president whose pitch is so tied to reforming politics that he forgot to take a lamentation of "super PACs" out of his stump speech amid the controversy on Wednesday, this is not a good situation.

Back when he was an underdog, Obama would have seized on such a blunder by an opponent's organization, and he did. Obama scoffed at notions of invisible walls between campaigns and outside groups and demanded that his opponents denounce the nasty tactics of their former aides.

Romney's campaign didn't pounce as quickly as Obama would have in 2008, first adopting a defensive crouch and insisting that had the woman lived in Massachusetts she would have been covered under Romney's 2007 health law.

But other Republicans got their indignation engines fired up and are prodding the political press to look at the chasm between what Obama has said about these kinds of attacks and what he is doing now. And Team Romney now seems to be moving from defense to offense on the subject.

Obama may yet be forced to denounce the ad. And if he does, he will have himself to blame because it was he who fostered the toxic attitudes toward his opponent inside Obamaland.

Chris Stirewalt is digital politics editor for Fox News, and his POWER PLAY column appears Monday-Friday on FoxNews.com.