Swing Vote is supposed to be another shaggy Kevin Costner vehicle, in which the star plays a beloved rumpled everyman with an aw-shucks grin. Yet Costner’s smile isn’t a natural fit for Bud Johnson, a bum of a single father whose vote, via complicated plot machinations, will be the deciding factor in the presidential election. The movie seems to find it charming that Bud’s 12-year-old daughter Molly (Madeline Carroll) has to wake him from a drunken stupor every morning and get him to drive her to school. The movie wants to be Mr. Smith Goes to Washington, but it’s more like watching James Stewart smile his way through The Lost Weekend.