House Appropriations Committee Chairman David Obey (D-Wisc.), a liberal lion first elected at the height of the Vietnam War in 1969, is set to announce Wednesday he will not seek re-election in November, according to a senior Democratic official. The move will deal a blow to Democratic chances of holding the northern Wisconsin seat.

Obey, 71, has called a meeting of his staff and issued a news release declaring a “major” announcement set for 1 p.m. on Capitol Hill. Obey, whose committee gavel gives him oversight of more than $1 trillion in annual federal spending, was facing his toughest re-election battle in years, as Ashland County District Attorney Sean Duffy (R) was running a promising campaign against him. The chairman’s plan to retire was first reported by David Rogers of Politico.

Republicans have focused their recruiting efforts on finding young, energetic challengers to veteran chairmen such as Obey. GOP recruits considered Duffy–a telegenic 37-year-old former star of MTV’s “Real World: Boston”–a textbook example of a challenger ready to take on an incumbent who took office before Duffy was even born.

“There is no question that David Obey was facing the race of his life and that is why it is understandable that the architect of President Obama’s failed stimulus plan has decided to call it quits,” said Ken Spain, a spokesman for the Republican campaign committee.

Obey has had a political lock on this seat, only drawing drew less than 60 percent of the vote in his 1994 and 1996 re-election battles. However, the district is much more evenly divided politically. While President Obama took 56 percent of the vote in 2008, Wisconsin’s 7th district split almost evenly in the 2004 and 2000 elections.

Rep. Obey will become the second chairman of a House Committee to retire this cycle. In late 2009, Bart Gordon, D-Tenn., Chairman of the House Committee on Science and Technology, announced that he would not seek re-election.