Swing Vote (2008)

Kevin Costner stars as Bud Johnson, an apathetic, beer slinging, lovable loser, who is coasting through a life that has passed him by, except for the one bright spot in his mundane existence, his precocious, over achieving twelve-year old daughter, Molly. She takes care of them both, until one mischievous moment on Election Day, when she accidentally sets off a chain of events which culminates in the presidential election coming down to one vote, her dads.

Suddenly, Bud Johnson, the nobody, becomes the voice for everybody when the world realizes that his vote will be the one that elects the next president. Politicians invade the small town of Texico, New Mexico and its unwitting inhabitants, waging war for Bud's vote.