Rep. Bart Stupak (D-Mich.) has continued to take a hammering over the recess for his controversial role at the heart of the health care bill’s abortion debate, prompting speculation that he is considering retirement.

Press Secretary Michelle Begnoche didn’t rule out such a scenario in a statement Wednesday, but she also indicated that “campaign plans are proceeding.”

“Every two years, Congressman Stupak discusses with his family and his constituents whether to seek reelection. He believes that is what the people of the First District of Michigan deserve,” Begnoche wrote in an e-mail.

But she added that the nine-term incumbent has “already acquired over a thousand signatures needed to file for reelection on May 11th” and “is pleased with the outpouring of support across his district.”

Critics on the left and right are already mobilizing to make it one of Stupak’s most difficult re-election campaigns should he decide to run for a 10th term. The political action committee Our Country Deserves Better, which is behind the Tea Party Express and its nationwide bus tour, has spent nearly $50,000 in the past few days as part of a $250,000 TV and radio ad campaign against Stupak. It has five tour stops and rallies planned in Stupak’s district this week.

Attacking Stupak from his other flank is the abortion rights group NARAL Pro-Choice America, which made $38,000 in independent expenditures opposing Stupak and supporting Democratic primary challenger Connie Saltonstall.

Should Stupak retire, it would offer Republicans a prime pick-up opportunity in his largely rural 1st district, which trends socially conservative. Residents voted narrowly for President Barack Obama in 2008 but backed President George W. Bush in 2000 and 2004.