“Where are you from? Russia?” the middle-aged woman asked matter-of-factly, as she walked toward her polling place in Seaside, California on Super Tuesday. She had been approached by a man wearing a Cossack Ushanka hat with a hammer and sickle pin, offering to buy her vote.

Neither she nor her daughter took the bribe, but they seemed intrigued, even charmed, by a guy meddling in our political process. After voting they returned with news that a friend was willing to switch to Donald T...