She was not alone. Tough votes for Obama’s health care plan have further complicated the re-election prospects of dozens of already vulnerable freshman and second-term Democrats. There’s even a chance the party could lose control of one or both houses in the midterm elections.

In districts and states where the overhaul was most controversial, town hall meetings have been replaced with tightly controlled business roundtables and other gatherings with voters.

In Nevada, first-term Democratic Rep. Dina Titus defended her vote for the health care bill in a newspaper piece she co-wrote and in a meeting with female doctors. Facing a vigorous GOP challenge from a Republican physician, she acknowledged treading carefully.

“It’s more of a teaching tour than a selling tour,” she said of her recent appearances.

Republicans dismiss the notion that voters opposed to the new law can be sold on it. They equate the overhaul to a “government takeover” of health care and blame it on one-party arrogance. The theme is central to House Republicans’ plan to cast the GOP as the party that will listen to what voters want, not pass bills the people oppose.

As lawmakers prepared to wrap up their recess and return to Washington, Republicans released a campaign spot featuring feet in flip-flopsand criticizing House Democrats who voted against the health care overhaul last fall but then voted for it on final passage.

Rep. Mark Schauer, a freshman Democrat representing southern Michigan, said there’s been some loud opposition at his meetings with voters, dairy farmers and small-business owners. But most people, he said, just want to learn more about the program.

“I think it’s my obligation to inform my constituents about what’s going on,” Schauer said.