Senator Arlen Specter has left the Republican party and joined the Democrats. But don't be fooled - his defection is neither an endorsement of the Democratic platform nor a rejection of the GOP. It's a matter of political survival, which he stated quite plainly in his interview on Meet the Press last Sunday:

"...I undertook a very thorough survey of Republicans in Pennsylvania with polling and a lot of personal contacts, and it became apparent to me that my chances to be elected on the Republican ticket were, were bleak. And I'm simply not going to subject my 29-year record in the United States Senate to that Republican primary electorate."

This was in response to David Gregory's reminder to Specter that only three weeks prior to his announcement that he was switching parties, he had advocated for bringing voters back into the fold of the GOP and insisted that our government needed the checks and balances of Republican representation. Apparently what Specter meant was his representation was needed.

Gregory went on to question Specter further about his reasons for the change, citing David Broder's Washington Post column: "The one consistency in the history of Arlen Specter has been his willingness to do whatever will best protect and advance the career of Arlen Specter." Specter replied that the changes in the Republican party, the increasing intolerance of moderate views, were also a key factor.

Washington Post columnist Eugene Robinson agrees that vote-getting is Specter's primary motivation:

"Specter's switch seems obviously based on arithmetic, not principle. About 200,000 Pennsylvanians left the Republican voter rolls between 2004 - the last time Specter had to run for reelection - and 2008...The Pennsylvania Republican Party is not just smaller but more conservative, and polls showed that Specter's apostasy on matters of Republican dogma made him all but defenseless against a challenge from the right."

There's arguably some degree of principle involved, otherwise Specter would have marched in lockstep with the rest of his (former) party. It was only when his continued dissent on certain issues threatened his chances of re-election that Specter decided to make the leap. But this threat was heightened by the changes in the Pennsylvania Republican electorate, as Robinson noted, citing the recent survey results from the Pew Research Center.

In fact, only the Independents have seen a significant increase in self-identification since 2004. Democrats saw a slight bump in 2008, but have remained relatively steady. Republicans, on the other hand, have dropped seven points over the past six years. In the past five months alone, both Democrats and Republicans have lost numbers (six points for the Democrats, 4 points for the Republicans), but Independents gained nine points. It's clear that voters are moving away from the Republican party, but unlike Specter, they're not heading directly across the aisle.

That's because they still agree with many of the basic tenets of the GOP listed by Robinson: "The Republican Party says it stands for individual rights, limited government, free enterprise, fiscal restraint, a strong defense - and it's hard to argue with any of those broad principles." I echoed these points myself - and my own frustration with the narrowing of the party - in a column about six months ago.

Maybe the Democrats are realizing that they can't take Specter at face value, and maybe the Republicans are washing their hands of him and commenting "good riddance". But we Independents are hoping that Specter's defection will take us one step closer to Republican party reform.