(NBC) -- With just 18 days left in the race for the White House and frustrated with what he sees as Mitt Romney's shifting positions on key issues, President Obama unleashed a new line of attack on Friday.
He claims his opponent has a condition.
"I think its called Romnesia," the president joked.
Mr. Obama is accusing Mitt Romney of swerving to the middle to attract women voters.
"If you say you're for equal pay for equal work, but you keep refusing to say whether you'd sign a bill that protects equal pay for equal work, you might might have Romnesia," he added.
The President then offered help.
"There's the good news! Obamacare covers pre-exting conditions," he laughed.
The President got big laughs, but Obama support in Virginia, the fourth biggest battleground state and site of Friday's rally, has dropped.
He's tied here with Romney, whose campaign said "women haven't forgotten" how they've suffered for four years.
Two new polls show former Governor Romney ahead nationally.
Two others show ties.
The NBC/Marist poll shows Romney trailing in Midwest states he needs to win.
So which team has the edge?
The NBC News/Marist poll suggests President Obama; he leads in Iowa, Wisconsin and Ohio.
If he wins those three he almost surely wins the election.
The last debate looms Monday in Florida.