By CNN Political Unit
John Dingell, the longest serving member of Congress in U.S. history, will announce Monday that he'll retire at the end of the year rather than run for re-election.
The 87-year-old Democratic congressman from Michigan told the Detroit News that "I'm not going to be carried out feet first," adding that "I don't want people to say I stayed too long."
Dingell told the Detroit News that his health "is good enough that I could have done it again. My doctor says I'm OK. And I'm still as smart and capable as anyone on the Hill." But Dingell went on to say that "I'm not certain I would have been able to serve out the two-year term."
Dingell added that the increased partisanship in the halls of Congress have diminished his love of his job.
"This is not the Congress I know and love," said Dingell. "It's hard for me to accept, but it's time to cash it in."
The retirement announcement from Dingell, the "dean of the House" for nearly two decades, was was confirmed to CNN by two Democratic sources with knowledge of the congressman's thinking.
Dingell has served in the House of Representatives for 58 years. He was 29 when he was first elected to Congress, in a special election to serve out the remainder of the term of his late father, who had held the seat since it was created in 1932.
Dingell, whose district is home to the Ford Motor Company, has long been a strong supporter of the auto industry, but he has also stressed environmental issues over the years. In his nearly six decades on Capitol Hill, Dingell's cast thousands of votes and played a key role in helping pass such signature pieces of legislation such as the Civil Rights Act, Medicare, the Clean Water Act, the Clean Air Act, the Endangered Species Act, and most recently in 2010, the Affordable Care Act, which is better known as Obamacare.
Dingell's news comes amid a slew of retirement announcements from many senior House and Senate members from both parties. Michigan is also losing longtime Democratic Sen. Carl Levin, who has served in the chamber for 35 years.
Michigan's 12th Congressional District includes several working class southern suburbs of Detroit known as the "Downriver" area. The district stretches west to include Ann Arbor, home to the University of Michigan.
Dingell grabbed 68% of the vote in his 2012 re-election. And Barack Obama won two-thirds of the vote in the district in the 2008 and 2012 presidential elections.
There's speculation that Dingell's wife of 38 years, Debbie, a longtime Democratic National Committee member, may run for her husband's seat, and if she launches a bid the move could discourage other Democrats from running.
CNN's Paul Steinhauser, Deirdre Walsh and Dana Bash contributed to this report.
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