I believe that the Bush campaign made a concerted effort to do the ground work to reach the rural areas, the red counties on that red/blue map from 2000. They decided that rather than spend money in the cities per se, they would drive up their numbers in these areas with organization and commitment.
Soros and the Dems tried to counter with massive registration in areas where the voter intent is not near as committed or strong, witness the "paid" volunteers turning in cartoon names.