WASHINGTON (CNN)  -- Veteran Pennsylvania Sen. Arlen Specter switched from the Republican to the Democratic Party on Tuesday, saying he has found himself increasingly "at odds with the Republican philosophy." Sen. Arlen Specter was expected to face a tough re-election battle in 2010. "This is a painful decision. I know I'm disappointing many of my colleagues," he said at a news conference announcing the move. "The disappointment runs in both directions. "I'm putting principle at the top of the list," he added. The switch puts Senate Democrats one vote shy of a filibuster-proof majority of 60 seats. They can reach the 60-seat mark if Al Franken holds his current lead in the disputed Minnesota Senate race.
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Pennsylvania Republican has been in the Senate for five terms
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Move would give Democrats 60-seat majority if Franken takes office
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Republican Party chief rips into Specter
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Republicans have been angry over his support of stimulus plan
Thanks to him, @placeholder will now be able to steamroll their big government agenda through the Senate.