The 10th District is Virginia in microcosm. Spanning the urban-oriented enclaves of Fairfax and the apple orchards around Winchester, it leans left on its eastern end and squats solidly Republican in the west. The area in between, around Dulles and the exurbs of Leesburg, bulges with Asian and Hispanic newcomers. “If you want to take the temperature of the country,” says Kyle Kondik of the University of Virginia’s Center for Politics, “this might be a good district to pick.”