It's no surprise that Molly Johnson—the 12-year-old (played by Madeline Carroll) at the center of Swing Vote, a comedy about a tight American presidential election—wants the world to be a better place.

Her dad, Bud Johnson (Kevin Costner, playing a caricature somewhere between trailer trash and a NASCAR dad), can hardly be bothered to take her to school, as he's too hungover from chugging beers the night before. She lives in a messy trailer in a small town in Texico, New Mexico, while her drugged-out mother is out of the picture.

In between babysitting her father, Molly obsesses over civics and the "social contract" of voting, and waxes on about democracy and the government taking care of people. (She puts those earnest Obama canvassers who've been knocking on your door to shame.) Her biggest dream? For her father to vote in the presidential election.

Shockingly, he drinks his way through election night. But thanks to a stunt by Molly, Bud's ballot ends up being the highly improbably deciding vote in the presidential race. The two are thrust into the political spotlight, and are wined and dined (er... beered and fished) by the candidates and the press, as Bud decides how he'll cast his replacement ballot. Molly, of course, is disgusted by the cynical, pandering politics. (Though not as much as I was disgusted by the rampant product placement in the film. Seriously, I think Budweiser underwrote Costner's character.)

If this were a typical film with an up-and-coming child actor, earnest Molly would be the supremely annoying, overacted, precious character. But Costner plays that part in this movie—he's good, but his character is obnoxious. Meanwhile, Carroll is great as a dry-yet-sweet Molly, saving an otherwise average and predictable film. You can't help but get wrapped up in her idealism, and she might even convince you that your vote counts.