ABC News' Teddy Davis reports:
Rep. Bart Stupak, the Michigan Democrat who led anti-abortion rights Democrats in the House during health-care negotiations, has decided to retire this year, according to a Democrat informed of his decision.
Stupak is expected to formally make an announcement later today.
Stupak's district, which covers much of Michigan's Upper Peninsula, will quickly become a major target for congressional Republicans. In 2008, President Obama carried the district by only two points: 50-48 percent over Sen. John McCain, R-Ariz. Former President George W. Bush carried Stupak's district by 7 points in both 2000 and 2004.
If Stupak had run for another two-year term, he would have faced challengers from both the Left and the Right backed by interest groups angered by Stupak's work on health-care reform.
Conservatives were angry with Stupak for backing the Democratic health-reform package. A few hours before the final health-reform votes were taken in the House of Representatives, Stupak called a press conference to announce that he and a block of anti-abortion rights Democrats were voting for health-reform because President Obama had agreed to issue an executive order assuring the new laws will keep taxpayer dollars from funding abortions.
Republican abortion-rights opponents thought the executive order was inadequate. They wanted the new restrictions to be contained in statutory language rather than an executive order.
Conservatives who oppose the health-reform package as an unwise expansion of government power were also vigorously going after Stupak.
Earlier this week, the conservative Tea Party Express launched a quarter million dollar ad campaign against Stupak. The group also scheduled a handful of stops on its bus tour in Stupak's district.
"Congressman Bart Stupak, you've betrayed our Constitution," says the narrator of the anti-Stupak ad being run by the Tea Party Express. "You sold us out on the health care vote and now it's time for you to pay the political price. Join the Tea Party express as we send Bart Stupak packing for an early retirement."
Watch it HERE.
Liberals were angry with Stupak for taking an abortion position which they thought would lead to fewer insurance companies including an abortion service in their health-care plans. Liberals worried that insurers would drop their abortion service in order to remain eligible to sign up the newly subsidized customers. NARAL Pro-Choice America, an abortion rights group, had endorsed Stupak's Democratic primary challenger, Connie Saltonstall.
The Republicans currently running in Stupak's district include physician Dan Benishek, former congressional candidate Don Hooper, and attorney Linda Goldthorpe. GOP officials in Washington think others might get into the race as well now that Stupak has decided to retire. The Michigan primary takes place on Aug. 3.