Powerful Democratic Congressman Rep. David Obey of Wisconsin announced his retirement today. The 71-year-old was first elected in 1969, and was known as a liberal stalwart who battled Republicans and pressured his own party from the left. Announcing his retirement, he called himself "bone tired." He leaves facing a tough Republican challenge. What are the political effects?

• Worrying Trends for House Dems Time's Jay Newton-Small calls this "a troubling sign for House speaker Nancy Pelosi for whom retention of the House grows more difficult with each retirement" and "the latest example of veteran Democrats deciding to withdraw rather than face tough reelections."

• Obey's Tough Race  The Minnesota Independent's Paul Schmelzer writes, "Obey faced the prospect of a tough election against Republican Sean Duffy, a former cast member of 'The Real World: Boston' and current Ashland County district attorney. Duffy had Sarah Palin's backing and, having amassed almost $300,000 last year, is Obey's best-funded challenger in more than a decade. This week Tim Pawlenty's Freedom PAC announced Duffy had won its crowdsourced endorsement."

• Can Dems Keep The Seat?  The Wall Street Journal's Susan Davis says, "Democrats were bullish on their prospects for holding the seat. ... The potential Democratic field to replace Obey is fluid ... but already names of potential candidates are emerging and a crowded, contested primary is possible." Obey's district "has been won by every Democratic statewide candidate in the past 10 years."

• ...It's 'In Play'  NBC News' Domenico Mantanaro evaluates the situation. "It puts Obey's Wisconsin seventh-congressional district seat in play for Republicans," he writes. "Projections for this fall's midterm show Republicans poised to make big gains in the House, perhaps coming close to or even taking over control of the House."

• ...GOP Could Win It  Conservative blogger John Hinderaker boasts, "It leans Democratic, but narrowly, having voted for John Kerry (51%) and Barack Obama (56%). In this season of discontent with the Democratic Party, a solid Republican candidate should have a good chance of winning the seat."

• Dems Lose Hard-Charging Liberal  Salon's Alex Pareene says of the "famously feisty" Congressman, "Obey is one of the most powerful liberals in Washington. He's been a major critic of the White House's Afghanistan policy. ... Rahm Emanuel (no stranger to being a complete dick to people) once said you weren't truly a member of Congress until Dave Obey rips you a new asshole. ... Obey also coined the classic Bill Clinton zing: 'If you don't like where he stands, just wait 10 minutes.'"

• Didn't Want To Be Minority Party  The Weekly Standard's John McCormack suspects that Obey "thinks the Democrats will lose the House and he doesn't want to go back into the minority. I wonder how many of his colleagues are having similar thoughts right now."

Want to add to this story? Let us know in comments or send an email to the author at mfisher at theatlantic dot com. You can share ideas for stories on the Open Wire.