If Alabama goes undefeated, I think he probably does win the award. This isn't like Trent's situation, in which he built up almost all the momentum in one season and then fell just short. AJ had a tremendous season last year, and deserved more consideration than he got, but he was still on a lot of people's lists for a good portion of the season. Being undefeated also means taking out A&M.
I think the three national championships aspect will weigh heavily on people's minds, and if he puts up numbers anything like last year, while Alabama is still in contention, it will be very hard to overlook him. AJ's chances went down the drain last year during the A&M game. Trent really lost his shot when Alabama lost to LSU. As long as Alabama is undefeated, AJ is likely to be one of, if not the favorite. It's also hard to imagine Alabama being undefeated without AJ, so this is probably as tied together as an Alabama teams hopes for a NC, and a player's hopes for a Heisman have ever been.