Could this be the year the G.O.P. goes populist? We should be skeptical, for two reasons.

First, there is some good evidence that Trump’s support has a ceiling. He isn’t the second choice of very many voters, and in head-to-head contests against varying alternatives, his performance is mediocre. Of course, he could gain momentum with enough wins, but for now, winning a majority of the delegates seems like a tough haul.

Second, the establishment is unlikely to give up easily against him. While the establishment vote has been spread out across three or four candidates for most of this cycle, it will eventually consolidate around a single candidate. That candidate will have virtually unlimited resources to test whether or not Trump’s support does have a ceiling. I suspect they will find it does.

But if this election season has taught us anything, it is that we shouldn’t settle on firm expectations for too long.