Usually one does not see Congressmen or Senators flipping parties to join the minority.  However, Politico’s Josh Kraushaar has a scoop that Blue Dog Democrat Parker Griffith of Alabama, a freshman in Congress, has seen enough of Nancy Pelosi’s leadership.  He will join Republicans in a move that has far more symbolic than substantive impact — for now:

POLITICO has learned that Rep. Parker Griffith, a freshman Democrat from Alabama, will announce today that he’s switching parties to become a Republican.

According to a senior GOP aide familiar with the decision, the announcement will take place in this afternoon in his home district in northern Alabama.

Griffith’s party switch comes on the eve of a pivotal congressional health care vote and will send a jolt through a Democratic House Caucus that has already been unnerved by the recent retirements of a handful of members who, like Griffith, hail from districts that offer prime pickup opportunities for the GOP in 2010.

The switch represents a coup for House Republican leadership, which had been courting Griffith since he publicly criticized Democratic leadership in the wake of raucous town halls over the summer.

Griffith’s district has been conservative for years.  His predecessor, Democrat Bud Cramer, almost found that out the hard way in the 1994 Republican landslide, barely hanging onto his seat.  After that scare, Cramer became a solid Blue Dog, and Griffith campaigned as someone who would follow in Cramer’s footsteps.

He must have understood that the Tea Party protests would mean disaster if he supported Pelosi’s agenda.  The move actually means a tougher ride for Griffith in the next year; he may have to shuffle his committee assignments, although the GOP is likely to accommodate him if possible.  He will also have to explain to his constituents why he switched after only the first year of his single term in office rather than just run as a Republican in the first place.  The Democrats in his district will paint him as an opportunist in 2010 when he runs for re-election.

However, he probably secured his chances for returning to Congress in 2011 with the flip.  The big question will be how many more Blue Dogs will make the switch in the next few months.  Will Griffith lead an exodus of conservatives and moderates out of Pelosi’s caucus?