Obama doesn't need Rural counties to win.
Obama can't lose them by too much or he'll lose the states they're in -- that's a fact. Keep in mind the trendlines -- he's doing 10 points worse than in 2008.
Nevada has a very small proportion of rural citizens. Colorado? The Front Range cities and their suburbs overpower the thinly-settled population of ranch country in the east. New Hampshire has its population concentrated along the I-93 corridor. Most people in Florida do not live on a ranch, farm, or orange grove. Ohio has the preponderance of its population in small-to-giant urban areas.