David Frum has an interesting post...

...about which Republican presidential candidates could win the nomination and which ones could win the general election. According to him, only Tim Pawlenty and Mitt Romney could do both. Frum's conclusion (my emphasis):

My guess is that the race boils down to a battle between the two of them.

Romney’s disadvantage in such a fight is Romneycare plus a general odor of insincerity.

Pawlenty’s disadvantage? The fact that he’d make an outstanding candidate for premier of a Canadian province.