Something strange is going on in Ohio. There don't seem to be any bumper stickers. I drive almost 100 miles a day on a major four-lane highway in northern Ohio. In the last two weeks, I saw one Trump bumper sticker in the parking lot of a grocery store, one Trump window-cling on a pickup truck on the highway, and one "I heart Hillary" bumper sticker at a rest stop. That's it. Four years ago, in August 2012, Romney and Obama bumper stickers were plentiful. It's a similar story with yard signs. A handful of Trump signs sprouted up during...