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President Obama has his super PAC to thank for a colorful and succinct new attack on Mitt Romney as the reverse of Robin Hood.

At a fundraiser Monday night in Stamford, Conn., Obama debuted the slam on his Republican rival, encapsulating a week-long critique of his proposed tax plan.

"He'd ask the middle class to pay more in taxes so that he could give another $250,000 tax cut to people making more than $3 million a year. It's like Robin Hood in reverse," Obama said. "It's Romney Hood."

The term, which drew the loudest applause and triggered a flood of buzz online, was coined not by Obama or his speechwriters but by a team of Democratic strategists working for Priorities USA Action, which floated the concept last week.

While Priorities USA Action and the Obama campaign are forbidden by law from formally collaborating, they have been known to take subtle cues from each other on message and tactics - something made a little easier when staff on both sides are former colleagues in the Obama administration.

Priorities USA senior strategist Bill Burton first surfaced the "Romney Hood" label for the presumptive GOP nominee in the subject line of an email blast to reporters on Aug. 1.

"The reverse Robin Hood economics in Mitt Romney's plan have finally been revealed," Burton wrote, citing a Washington Post report on the new Tax Policy Center analysis of the governor's tax plan.

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Burton today credited the creative collaboration of his staff, including strategist Paul Begala, with coming up with the bumper-sticker frame on Romney's economic vision. He suggested it was a flattering coincidence that the president has adopted the line for his stump speech.

Obama campaign spokesman Ben LaBolt wouldn't address the super PAC inspiration for the "Romney Hood" line, adding only that the phrase is "pretty much self-explanatory."