The theory seems to be that all of the front-runners are flawed in some way, which is undoubtedly true. But if one of the front-runners flops in some way once the campaign actually begins, I don’t see why it wouldn’t be one of the other front-runners who would pick up their slack: if Sarah Palin’s campaign gets off to a poor start, for instance, it is probably Mr. Gingrich — not Mr. Pawlenty or Mr. Thune — who would get first dibs on her votes…

The other potential flaw in the analysis of candidates like Mr. Pawlenty and Mr. Thune is that some seem to think it an asset that they are bland and unobjectionable. In a primary election that isn’t an asset, but a liability. A primary election isn’t a reality show in which candidates are eliminated one at a time for failing some challenge. Instead, voters pick the one candidate whom they most like, rather than the one they most dislike; a candidate who has strong favorables and strong unfavorables is going to be more people’s first choice than one whom everyone feels indifferent about. Someone with a more distinct and provocative brand — like Gov. Chris Christie of New Jersey or Representative Paul Ryan of Wisconsin — might stand a better chance in an underdog role, although neither is likely to run for president in 2012.