White Republicans from those counties have been moving further out of the city, to places like Cherokee, Forsyth, Barrow, etc which have always voted something like ~75% GOP, but now have twice as many voters as before. These voters are the GOP's base in the state; heavily motivated by cultural issues and taxation. And they hate Obama.
As someone interested in sociology/political science this is something I have been fascinated by. What politically speaking separates a county like Loudoun, VA and Forsyth, GA?
Loudoun is a very wealthy county (in fact I think it might be the wealthiest in the country). It is a very exurban county with a lot of heavy growth. It is located in Virginia, which for the sake of the argument, is a southern state. In recent years, the county has been competitive for both parties.
Forsyth could have a similar spin. It is a very exurban county, a lot of new growth in recent years, a wealthy county, and in a southern state. But it gave McCain something like 78%, which is unheard of.
