I think many pundits are making a tactical mistake in how they attack Trump. They spend a lot of time making fun of him.
Now, Trump is very mockworthy. He richly deserves the mockery that's heaped upon him. However, too much of that plays into his hands. It enables him to cast his critics in the role of elitists. The Republican establishment. Folks who support Jeb or Kasich. The Brie and Chablis crowd. Trump can then contrast himself as the tough guy who takes no guff, who stands up to the Establishment–unlike those effete snobs.
Problem is, the only thing Trump stands for is Trump. His only interest is self-interest. Promoting his company and his one-man personality cult.
Critics should focus on his flip-flops and his business failures. Trump is a classic flimflam man. There's nothing there.
In some ways he reminds me of Il Duce. It's just a put-on. Strutting about like a rooster. King of the barnyard.