If you line up the four Virginia counties that surround DC...they all vote heavily (over 70 percent usually) Democrat. There are three or four other counties around the state that typically lean or go that direction as well....and then the rest of the state of Virginia is fairly Republican. This has been a long time in development and a lot of this has to deal with the suburban attitude of northern Virginia. You can also look at the amount of money that those four counties demand from the state (which fairly said...they deserve because of the significant state taxes that come from that region and the salaries associated with them).
Well all those Government working Parasites who sacrifice by working for the Government have to Live somewhere and there sure are not fewer Government Parasites since Obumbo has been President.