Dave Weigel wonders whether the Pennsylvania ex-Senator will be the GOP’s frontrunner in four years’ time, considering that “the runner-up of the last Republican primary always starts off with an advantage. McCain 2008. Dole 1996. Bush 1988. Reagan 1976.” What’s more, assuming presumptive nominee Romney loses to Obama this year, wouldn’t back-to-back failures by moderate Republicans open the door to getting a right-winger the nomination next time?

Probably not. The same list that testifies to the GOP’s propensity for nominating runners-up also shows what kind of Republican typically gets the nomination, namely the kind that includes Bush, Dole, McCain, and Romney. (Bush II doesn’t make the list as a runner-up, but he fits the ideological pattern — and anyway, quite a few voters initially thought he was his father.) The Republican base is not primarily conservative, it’s primarily Republican, and while it’s happy to throw rhetorical bones and even symbolic scraps of legislation in the direction of economic conservatives and the social right, what party loyalists are most concerned about is winning elections. Which hasn’t proved to be Santorum’s strong suit.

Instead, I expect that for the first time since 1968 the GOP won’t have an heir apparent. That by itself might be a terrifying enough prospect to induce some unusual behavior in the party-loyalist base, but I don’t think it will send them running to Rick Santorum.