WASHINGTON - When Arlen Specter ran for Philadelphia district attorney in 1965, he proudly proclaimed himself a "Kennedy Democrat," and said he was running as a Republican to take on what he saw as the corruption of the city's then-legendary Democratic machine.
Forty-four years later, Arlen Specter has come full circle.
In announcing his switch to the Democratic Party on Tuesday, the maverick Pennsylvanian was doing more than trying to save a political career jeopardized by the increasing conservatism of the Republican Party. He was also ratifying a decisive shift in American politics.
The GOP in his home state had once been a bastion of moderates and liberals, including William Scranton, Hugh Scott and Richard Schweiker. In the age of Barack Obama, Republicans of that stripe are flooding into the Democratic Party. Specter is not a leading indicator. His conversion is the culmination of an inexorable trend.
In a sense, Specter's departure is a victory for conservatives who, since the days of Barry Goldwater, have been intent on purging liberals from the GOP. The raw political fact is that Specter was in grave danger of losing a Republican primary to former Rep. Pat Toomey, an anti-tax activist. One Democratic strategist reported seeing polling that showed Specter less popular among Pennsylvania Republicans than President Obama.
Conservatives had once hoped that creating an ideologically pure party would put them on the path to a majority. But they must now worry that the Republicans' continued rightward drift is putting the party at odds with a moderate to liberal mood that pervades the country almost everywhere outside the Deep South. And Specter's switch would give the Democrats a filibuster-proof majority in the Senate, assuming that Minnesota's Al Franken eventually takes the seat for which he now leads after an extended recount.
At the instant of his conversion, Specter transformed himself from a political underdog into a favorite for reelection in 2010. That's because Pennsylvania became far more Democratic in the final years of George W. Bush's presidency. In 2004, Democrat John Kerry carried the state by roughly 144,000 votes. Barack Obama's margin in 2008 was more than 620,000.
Reflecting a trend across the Northeast and Midwest, Democrats have posted especially strong gains in the suburbs, particularly in the counties around Philadelphia. Those had once provided a base for moderate Republicans -- notably Specter himself. They are now helping to pad Democratic margins, and Specter is hoping they will support him in his new political incarnation.