Evan McMorris-Santoro April 9, 2010, 12:53 PM

After making his official retirement announcement today, Rep. Bart Stupak (D-MI) gave a nod to state Rep. Mike Lahti to succeed him — though he stopped short of formal endorsement. In the speech from his Michigan district, Stupak said he’ll finish out his term in office, but not seek reelection to the seat he’s held since 1993.

“It’s time to begin a new and exciting chapter,” Stupak said. “I will always serve the people of the First District, but I have chosen not to continue to serve as their congressman.”

Stupak said his leaving doesn’t mean the seat will fall into Republican hands, despite demographics and GOP confidence that the district is now a prime pickup opportunity.

“A lot of people could do it,” Stupak told a reporter when asked if Democratic candidate could win the seat. “People like Mike Lahti would do a great job.”

Lahti, a conservative Democrat, was among those on the short list of candidates we reported on earlier today.

Stupak said it wasn’t “one thing” that lead him to make his decision, “it was a number of things.” But he suggested that his vote for health care reform, which drew fire from tea party groups, was a final victory in a career that has included opposition to the Iraq War and fighting to limit abortion rights in America.

“After 18 yrs, together we’ve accomplished what you sent me to Washington to do,” he said. “Health care for all Americans.”

Stupak promised to work hard to keep the seat in Democratic hands. He said the timing of his announcement gives Democrats “ample opportunity” to gear up campaigns in advance of the May 11 filing deadline in Michigan.

Though Stupak mostly chose not to engage with the tea party groups and anti-health care reform conservatives — who have bombarded him with criticism since he cut a deal with Democratic House leaders and the White House over abortion language in the bill — his wife did not. Introducing her husband at the speech today, Laurie Stupak said that the calls and letters from angry conservatives had left their mark.

“During the recent health care debate, our offices and home were deluged with calls,” she said. “Unfortunately some of those calls were vulgar cruel and insulting.”

Laurie Stupak said “95 percent” of the calls had come from outside the district, and she defended her husband against charges from the right that his vote for the health care bill betrayed his anti-abortion convictions.

“He has always been pro-gun, pro-life and pro-health care,” she said.

Bart Stupak