If it seems needlessly complicated to suggest that two effects — grassroots muscle and general party branding — have to be invoked to explain the GOP’s unsuccessful presidential branding, consider this: if the only effect in play were the strength of grassroots right-wing constituencies, you wouldn’t expect the party to consistently nominate moderates like both Bushes, Dole, McCain, and Romney. None of those nominees had impeccable conservative credentials — far from it. But once they got the nomination, they didn’t run as the moderates they were; most of them sold themselves as being at least as right as Reagan, even in the general election. At least since 2004, this is because the party has pursued a base strategy: an attempt to eke out a narrow win by getting more Republicans to the polls than Democrats, with independents — a small and difficult-to-market-to demographic — basically ignored. The party tries to leverage its regional identity and regional organization into presidential victory. It has failed four times out of five.