Several Democrats in competitive seats will face tough questions about why they supported the bill after opposing it during the House’s first vote in November — a list that includes Kosmas, Markey and freshman Ohio Rep. John Boccieri, who explained his vote in a news conference in front of the Capitol that was televised live on CNN…

“Members who switched from no to yes will really have the difficulty,” predicted Tom Davis, the former Virginia congressman who chaired the NRCC. “I just think switching from no to yes makes you look like you were strong-armed.”

Larry Sabato, a University of Virginia political scientist, said those Democrats who went the other way — switching from yes in last fall’s health care vote to no on Sunday — will not be able to escape the heat, either.

Members in this category include Reps. Zack Space of Ohio and Michael Arcuri of New York, both of whom represent districts that voted for Bush twice.

“I’ve listened to some of the flippers, and they have very good explanations for their change of heart. Problem is, [Sen.] John Kerry had a good explanation for his: ‘I voted for it before I voted against it.’ Few voters are going to listen to their paragraph-length explanation,” said Sabato.