Image Credit: Susan Walsh/AP Photo

Standing in front of a bleacher consisting entirely of women at George Mason University today, President Obama introduced a joking new line of attack designed to paint his GOP opponent's pivot to the center as insincere and deceptive.

"Now that we're 18 days out from the election, Mr. 'Severely Conservative' wants you to think he was severely kidding about everything he said over the last year," the president said. "He told folks he was the ideal candidate for the Tea Party, now he's telling folks, 'What? Who me?' He's forgetting what his own positions are. And he's betting that you will too."

Continued the president, "he's changing up so much and backtracking and side stepping we've got to name this condition he's going through.

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"I think it's called…'Romnesia,'" the president said to cheers and laughter.

"I'm not a medical doctor, but I do want to go over some of the symptoms with you because I want to make sure nobody else catches it," the president said in the battleground state of Virginia, where recent polls show Mitt Romney with momentum.

"If you say you're for equal pay for equal work but you keep refusing to say whether or not you'd sign a bill that protects equal pay for equal work, you might have Romnesia," the president said, sounding not a little like comedian Jeff Foxworthy.

"If you say women should have access to contraceptive care but you support legislation that would let your employer deny you contraceptive care, you might have a case of Romnesia," the president said. "If you say you'll protect a woman's right to choose but you stand up at a primary debate and say that you'd be delighted to sign a law outlawing that right to choose in all cases, then you've definitely got Romnesia."

Moving on from issues he was raising to try to win over more women voters - Romney is polling better with women than previous Republican presidential candidates - the president said Romnesia extends to "other issues. If you say earlier in the year, 'I'm going to give a tax cut to the top one percent' and then in a debate you say 'I don't know anything about giving tax cuts to rich folks,' you need to get a thermometer a take your temperature, because you probably have Romnesia.

"If you say that you're a champion of the coal industry when, while you were governor, you stood in front of a coal plant and said 'this plant will kill you' -"

The crowd, for this one, chimed in "you probably have Romnesia," prompting the president to laugh and say, "that's some Romnesia."

Said the president, "if you come down with a case of Romnesia and you can't seem to remember the policies that are still on your website or the promises you've made over the six years you've been running for president, here's the good news: Obamacare covers pre-existing conditions!"

The crowd cheered ebulliently.

"We can fix you up!" said the president, who trails by seven points in the latest Gallup Daily Tracking Poll. "We've got a cure! We can make you well, Virginia!… This is a curable disease!"

-Jake Tapper and Mary Bruce