"Where were the Romneys during the wars?" he said. "Judge Moore has more integrity in his pinky finger."
Steve Bannon rallies for Roy Moore in Alabama →
Mr. Romney, the GOP's 2012 nominee, said last week that he has no intention of voting for Mr. Trump in the general election.
Herman Cain to #NeverTrump crowd: 'Get your egos out of the way' →