But with Christie weakened, there are suddenly almost as many paths as there are plausible candidates.

The New Jersey governor could still follow McCain’s 2008 path to victory, but he could also be marginalized, Huntsman-style, as a “centrists only” candidate — especially if a Scott Walker, a Paul Ryan or a Jeb Bush consolidated the support of moderate conservatives.

Then there’s the potential Ted Cruz coalition, which could look like Reagan redux: secular conservatives plus religious conservatives to start, and then just enough moderate conservatives to win. But Cruz would need to consolidate the religious faction early, which is why he should be hoping that Huckabee and Santorum decide to forgo another run.

And then there is the fascinating case of Rand Paul, who has a potentially formidable base in two factions that don’t usually ally — moderates who like his social libertarianism and secular conservatives who like his economic views.