Just incase you live under a rock with no TV, radio, or Internet, Sen. Arlen Spector (R) is now a (D) for Pennsylvania.

"Since my election in 1980, as part of the Reagan Big Tent, the Republican Party has moved far to the right. Last year, more than 200,000 Republicans in Pennsylvania changed their registration to become Democrats. I now find my political philosophy more in line with Democrats than Republicans." 

Check out the whole store via Salon.com: http://www.salon.com/politics/war_room/feature/2009/04/28/specter/.