Arlen Specter, the former moderate Republican Pennsylvania senator who switched to the Democratic party in 2009 and now performs standup comedy, told a joke about Mitt Romney on MSNBC's "Morning Joe" that stunned the other panelists.

Co-host Mika Brzezinski asked him about what he thought was the future for the Republican party.

"Well, the Republican party has moved so far to the right, you can't recognize Mitt Romney. What Mitt Romney will appear in October?" said Specter.

Paraphrasing a recent joke by Bill Maher, Specter said, "Mitt Romney has changed positions more often than a pornographic movie queen."

The joke drew awkward chuckles, and co-host Joe Scarborough defended the joke as something a comedian would say, and then he cut to footage from Specter's standup routine.

Throughout the interview, Specter assailed the wings of both parties for challenging moderates and primaries and decried the decline of bipartisanship. Specter was defeated in a 2010 Democratic primary for U.S. Senate by Joe Sestak, who lost to Sen. Pat Toomey (R-Pa.) in the general election.

The reason for Specter's recent media tour is that he has a new memoir out, "Life Among The Cannibals," detailing his career in the Senate. The Huffington Post's Amanda Terkel found the five steamiest passages, including meeting Sarah Palin, going in a hot tub with late Sen. Ted Kennedy (D-Mass.) and working out with Sen. John Thune (R-S.D.).

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