Third — and this is what I missed — Trump is right now over-performing versus the RealClearPolitics polling average, thus dealing a blow both to the “Trump people won’t turn out” and the “Trump as Buchanan” theories. He pushed through the Buchanan vote ceiling and decisively won in a high-turnout primary. All of this bodes well for him as his campaign moves South, where he’s polled strongly virtually from the start.

In the South, voters traditionally like conservatives and they like populists, so the table looks set for an epic clash between Trump and Cruz in South Carolina — with Trump holding the early edge. The only thing that could shake that dynamic is if one or more of the “establishment lane” candidates decides to give up their own presidential dream to stop Trump. But who will go first?