An open House district in Virginia stretching 250 miles up from the North Carolina state line to the outer Washington, D.C., exurbs will help test just how blue the commonwealth has become.

The 5th District is open because the sitting Republican, Rep. Denver Riggleman, lost his fight for renomination at a party convention early in the summer. Conservatives said Riggleman, a strong supporter of President Trump, had strayed ideologically after performing a same-sex wedding for a pair of staff members.