More bad news for Minnesota Republicans: Longtime GOP Congressman Jim Ramstad announced today that he would not run for re-election next year. The news is expected to spark a lively endorsement fight in both parties, as a number of candidates immediately expressed their interest in the seat.

On the GOP side, the list includes 2002 gubernatorial hopeful Brian Sullivan and last year’s Republican endorsee for secretary of state, Jeff Johnson. Also considering a run is State Sen. Geoff Michel of Edina.

DFLers Andy Lugar, who lost a bid last year for Hennepin County attorney, and State Rep. Melissa Hortman of Brooklyn Center quickly threw their hats into the ring, and two others — former State Sen. Ember Reichgott Junge and Buck Humphrey — are likely to announce their intention to run in the days ahead.

Last year, the centrist Ramstad beat talk radio personality Wendy Wilde by a predictably wide margin (65-35) during a year when the DFL dominated at the polls. But with his retirement, the DFL has its best chance to regain this seat since 1959, the last of Roy Weir’s six terms. Since then, Republicans have dominated, with Clark McGregor, Bill Frenzel, and Ramstad serving the affluent western metro district.

Among the likely DFL challengers, Junge may be the most able to pitch the kind of centrist political positions that would resonate with voters here. But she will have to improve upon her performance in last year’s 5th District DFL contest, during which her campaign organization and her performance on the stump left much to be desired. Perhaps more troublesome could be the charges of political opportunism that are likely to descend on the former state senate majority leader, who does not currently reside in the district.

Lugar, a former federal prosecutor, ran a sterling campaign last year only to be steamrolled by Mike Freeman’s superior name recognition and (arguably dicey) resume. Whether he’s yet recovered from that particular nightmare will have much to say about whether he’s ready for another bruising campaign.

Humphrey is, well, a Humphrey. But he’s yet to display much of his old man’s political instincts — or discipline.

Our guess here is that Sullivan will prove to be too right-leaning to make the grade here and that Michel may be a better fit than Johnson. Any way you slice it, though, this cannot be good news for the already-battered GOP.