The decision of Sen. Arlen Specter of Pennsylvania to switch to the Democratic Party, announced Tuesday, is a major political game changer -- providing Democrats with what may be the 60th vote in the Senate needed to break Republican filibusters as the Democrats try to act on the Obama administration's legislative agenda.
Mr. Specter's decision will also put a spotlight on potential disagreements within the Democratic Party on issues ranging from the mounting federal deficit to defense spending priorities. The Democrats will have only themselves to blame for any voter dissatisfaction with future congressional actions.
"I now find my political philosophy more in line with Democrats than Republicans," Mr. Specter said.
If Al Franken wins, as expected, in the court dispute over his election to the Senate from Minnesota, and Mr. Specter begins caucusing with Democrats, Democrats would have 60 votes and be able to block any Republican effort to derail legislation.
"It helps on everything," said Sen. Dianne Feinstein, Democrat of California. "This is a substantial change."
Specter's decision could be more consequential because it came just as the Senate was beginning work on health care reform legislation, one of President Obama's key goals this year. The president has recently convinced congressional leaders to set the stage for approval of major health care reform legislation this fall by a simple majority vote in the Senate -- avoiding a Republican filibuster. But that controversial course may now not be necessary.