At the tailgate outside Jack Trice Stadium in Ames on Saturday afternoon, hundreds of football fans gathered around a tent hosted by the Republican party of Iowa, hoping to see Donald Trump. They shouted for hours, tussled with protesters and then cried “Trump, Trump, Trump” when they saw a helicopter they thought he might be on. The mostly male crowd gripped beers, constantly asking when the real estate mogul and Republican frontrunner would appear. But they didn’t seem bothered by the fact he was running late. One college-aged girl said: “Donald Trump is just like Hilary Duff [actor and singer...