In a statement, Senator Collins takes a very different tone on the Specter switch than her colleague, blaming local politics for the defection rather than an increasingly ideological Republican Party:

"I have great respect for Senator Specter who has worked hard for many years on behalf of the people of Pennsylvania.

"I am, however, extremely surprised and disappointed with his decision to leave the Republican party.

"Senator Specter has long been a leading moderate voice in the Senate, and I believe that his decision is more a reflection of Pennsylvania politics than anything else."

The Huffington Post has more from Snowe, along the same lines as her earlier comments:

"Specter's switch to the Democratic Party "underscores the blunt reality" that the GOP is not a welcome place for moderates, she said.

So far, she said, she's staying put. "I believe in the traditional tenets of the Republican Party: strong national defense, fiscal responsibility, individual opportunity. I haven't abandoned those principles that have been the essence of the Republican Party. I think the Republican Party has abandoned those principles.

She added that being a Republican is simply part of who she is. "It's my ethnic heritage, Spartan side, that continues to fight," she said.