The Romney-Gingrich Electability Conundrum

Perhaps the thinking behind present polls goes something like this:

If Mitt Romney is the most electable, and Newt Gingrich is unelectable, Mitt Romney should easily beat Newt Gingrich.

But Newt Gingrich just beat Mitt Romney in South Carolina, and may do so again in Florida.

So maybe it's Mitt Romney who's not electable, or less electable than Newt Gingrich? And maybe Newt's not so unelectable after all?

I recognize that the general election is a different ballgame, but it's difficult for me to see how a candidate who barely squeaks past Newt Gingrich will be inspiring either a great deal of confidence in or the robust support of the Republican base. But perhaps that is Romney's problem to begin with.