The background music, the black dude doing backflips, even the length of the ad works to its effect - by the time the thing is through, voters will be sick of it.
By time the commercial ends, the average swing voter will indeed have flipped because of this commercial... to another station. The only people idiotic enough to watch this ad to the very end will be political geeks like us, who will be unlikely to have been affected by it at all. At best, it might help stir the faithful, but it won't convert the sinners.