What most impressed me about the Louisiana event was how declining interest in the nominating contest produced a primary electorate sufficiently rarefied as to produce a fantasyland for Santorum. Half of those participating in the primary defined themselves as "very conservative." Half called themselves "strong supporters" of the Tea Party. Three-fourths were over the age of 45. Two-thirds claim to attend worship services every week. 

Indeed, Romney lost every demographic in the state, except among voters making more than $200,000 per year. Aaron Blake looks ahead: