Parker Griffith, a Freshman Representative from Alabama, will announce today that he is switching from the Democratic to Republican Party. The change comes amidst the long and bruising battle within Congress over health care reform, which frequently splits along party lines. Griffith, a doctor, was one of the Blue Dogs, a coalition of conservative Democrats from Southern states. Reaction has been sweeping and immediate, with observers wondering why he did, what it means for Congress, and whether it will effect health care.

• Only Matters As Symbolism  So argues Talking Points Memo's Eric Kleefeld. "Griffith's party switch will provide Republicans with some rhetorical muscle about people rushing to their banner against the Democratic agenda, but in practical terms in Congress it won't mean much for Democrats. Griffith was a consistent vote against the Democratic agenda this whole year -- as examples, he voted against the stimulus, against the cap-and-trade bill, and against the health care bill."

• A Reminder That Supermajorities Don't Last  Matthew Yglesias calls the immediate meaning "nil" but notes, "the implications are still bad. People rarely volunteer to join the minority. Mostly, though, I think this is a reminder that the Democrats’ current huge majority with 257 members isn’t remotely sustainable. To get a majority that big you need to win a lot of districts you just can’t reliable win. Substantial losses in 2010 and/or 2012 are basically inevitable."

• 'Running Dogs'  National Review's Stephen Spruiell celebrates:

Retirements: Dennis Moore, John Tanner, Bart Gordon, Brian Baird.

Defections: Parker Griffith.

We need a ticker to keep track of these.

• More To Come?  The Washington Post's Chris Cillizza wonders. "It remains to be seen whether Griffith is an isolated case or the first of several Democrats to make the switch. There are 49 Democrats currently representing districts that Arizona Sen. John McCain (R) won in 2004 including 11 where Obama got under 40 percent of the vote. [...] Griffith's switch is the first in the House since 2004 when Louisiana Rep. Rodney Alexander became a Republican."

• GOP Should Oust Him!  Conservative blog RedState chief Erick Erickson welcomes Griffith to the party. "Here are Griffith’s earmark requests. He voted for Pelosi for Speaker. He’s actually been more regularly with Pelosi than Jim Marshall (D-GA). We can pick this guy off and get a real Republican in that seat."

• Democrat Dollars For His GOP Campaign  Politico's Josh Krausharr reports, "Griffith now has $619,000 in the bank to run as a Republican, a total boosted by contributions from several of the Democratic Party’s more liberal leaders. The political action committee of House Majority Leader Steny Hoyer donated $10,000 to Griffith’s reelection this year, and even [Speaker of the House Nancy] Pelosi chipped in $4,000."

• 'Cue The Crowing'  Talking Points Memo chief Josh Marshall rolls his eyes. "Guess he's probably a no on health care."

• How Dems Could Have Prevented  Wonkette's Juli Weiner has an idea: "Should have called 'No Switchsies.'"

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