Say what you want about either lead candidate, this certainly doesn't help Vince Young: ABC coverage map
The two teams' games are being played at the same time, and Young's mostly cornered in a region he'll clean up anyway. He does touch some of the border south and midwest voting regions, but is mostly locked into the southwest.
Meanwhile, Bush ranges all through the western region, through much of the midwest, and into almost the entirety of the northeast. Huge.
Plus, the energy around USC's final schedule is a little more significant, they have rivalry games against California, with all the storyline that goes with that, a game against self proclaimed world beaters Fresno State after that, then on championship weekend, a game against Rival UCLA that isn't as big as it was but remains a prominent CFB rivalry that people throughout the country will want to watch. Meanwhile, Young has the equivalent of games against the JV squad, with Kansas, Texas A&M and the Big Twelve Championship against a Colorado team they've already crushed.
I know HP says that at this time Heisman voters are not paying attention, but however true that is, Reggie Bush is certain to gain some advantage thanks to the scheduling Gods. I think a similar phenomena worked against Adrian Peterson last year, as he played a few meaningless final games last year against Baylor and Colorado while Matt Leinart finished up against Notre Dame and UCLA.
Keep in mind much of the final outcome boils down to how candidates perform with voters outside their own regions.