Wyoming, that's the place to go when the zombi apocalypse starts. Let me see...if I drive at 25 mph I can get 100 mpg. If I carry 10 gallons of extra fuel, maybe I can make it to Wyoming from Florida.
I actually find it quite remarkable, with the obvious exception of Alaska and that Wyoming/Montana/Nebraska/Dakotas area, how similar this map is to a normal one. You have a remarkably-evenly-spread population.