John Dingell's wife to seek his U.S. House seat: source

WASHINGTON (Reuters) - Debbie Dingell, the wife of retiring U.S. Democratic Representative John Dingell, will announce on Friday that she will run for his Michigan congressional seat, according to a close friend of hers, who asked not to be identified.

"I can confirm that she will announce on Friday that she will seek election to the 12th District" congressional seat, the source said on Tuesday.

John Dingell, 87, who has served longer in the U.S. Congress than anybody else in history, announced on Monday that he would not seek re-election in November.

Debbie Dingell is a Democratic Party activist with deep ties to General Motors Co.

If she were to win the seat, Michigan voters would continue an unbroken line of Dingells serving in Congress that began in 1933 when John Dingell Sr. was first elected to the House and was replaced by his son 58 years ago.

Democrats believe they will easily hold the seat in November's election. The racially mixed congressional district, which includes the auto manufacturing center of Dearborn outside of Detroit, voted overwhelmingly for Obama in his successful 2012 re-election.

(Reporting by Richard Cowan; Editing by Peter Cooney, Toni Reinhold)