A piece in Politico today proffers a few explanations for Blanche Lincoln’s moderately surprising win in Arkansas’s Democratic Senate primary. One of the key take-aways, say reporters David Catanese and Shira Toeplitz, is the importance of authenticity, which leads to this little digression:

It’s not a coincidence that two of the four House and Senate incumbents who have been ousted this year recently switched parties: Rep. Parker Griffith in Alabama and Sen. Arlen Specter in Pennsylvania. The latter of two blatantly said he switched parties to “enable me to get reelected” – a line that was used against him repeatedly in the primary.

Boiled down to its essentials, party-switching is a matter of character and authenticity. And those traits appear to be exceptionally important in helping incumbents weather this year’s storm.

Well, maybe. Certainly Specter’s breathtakingly candid—and, ultimately, incorrect—remark didn’t do anything to boost his standing.

But a characterological explanation for why party-switchers aren’t winning elections may be a solution in search of a problem. Politicians switch parties because they’re afraid they’ll lose an election! Specter jumped ship because he saw his connection with Pennsylvania’s Republican base fraying. Griffith switched teams because he didn’t think voters in his district would elect a Democrat to federal office in 2010. They took the route that offered them the best chance to staying in office, and it didn’t work out, in part because neither pol had a natural base in his new party.

That lack of a base might be seen as a result of inauthenticity, but it’s as much a function of their political biographies. And while the act of party-switching may have revealed character weakness, it just as clearly revealed pre-existing electoral weakness. After all, Specter and Griffith could’ve manifested their steadfast authenticity and strong character by remaining in their parties—and in the end, would’ve met the same fate.

Greg Marx is a CJR staff writer. Follow him on Twitter @gregamarx.