A long time from now if they keep pushing candidates statewide like rehashes (Gillespie) and Confederates/wackjobs (Stewart/E.W. Jackson). They might be able to win if they max out downstate but that is an outside chance with the growth of NoVA and Tidewater holding that possibility at bay.
The only chance for the VA GOP to win again is if they put up a moderate candidate in the mold of Jon Huntsman. Even then, it would be a fight.
Judging by Corey Stewart's near-win, and his passionate following of white nationalists and neo-Confederates that seem to comprise at least half the Virginia GOP's activist base, it will be very difficult for Republicans to choose anyone other than candidates like him in the future. Ed Gillespie is, I think, the last remotely mainstream Republican to win the gubernatorial nomination for a long time to come.
I would like them to become a more genuinely multiracial and multiethnic party in the future, but how they get there from here is truly a Gordion's Knot I'm not sure they will prove capable of untying for awhile.