His age.Â Campaigns are grueling - not sure he has the energy for one.Â His recent touchy-feely scandal.
Well, Gravel does run, and he's 88 and needs a cane to walk. So that's not necessarily something that would keep him out.
As for the scandal, it was very short. I don't think it will harm much on the long run.
The Nintendo eShop rating Thread: http://gamrconnect.vgchartz.com/thread.php?id=237454