Obama recently has emphasized the Romney-is-extreme message.
He told Rolling Stone, "You have a Republican Party and a presumptive Republican nominee that believes in drastically rolling back environmental regulations, that believes in drastically rolling back collective-bargaining rights, that believes in an approach to deficit reduction in which taxes are cut further for the wealthiest Americans and spending cuts are entirely borne by things like education or basic research or care for the vulnerable."
"I don't think their nominee is going to be able to suddenly say, 'Everything I've said for the last six months, I didn't mean,'" Obama told the magazine.
The president said in a Twitter message recently, "If you think Mitt Romney isn't extreme on women's issues, think again." It linked to a video criticizing Romney on several issues, including access to birth control.
Charlie Black, an informal Romney adviser, said that all during the GOP primary, Americans heard Gingrich, Santorum and others say Romney isn't conservative enough. Now, when Obama's allies say Romney is far too conservative, it will ring false and confusing, he said.
"It's all they've got," Black said. "They can't run on his record."
Democratic strategists say they expect Obama's campaign to refine and focus its criticisms of Romney over time, as polls and focus groups reveal each candidate's softest spots.
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