Assuming they lose the Senate this year, Republicans don't even need VA in 2018 to win back the Senate then. Someone like Barbara Comstock could win, but I'd rate this race Tilt D for now.
Republicans can win 10 seats in 2018 assuming Clinton wins (which is likely),
I'm sure they will screw up some races because this is the Republicans so they will end up picking up from 6 to 9 seats, 8 would be my guess right now.
lol
North Dakota, West Virginia, Montana, Indiana, and Missouri are five easy pick ups if Hillary's President. Florida, Virginia, Ohio, and Pennsylvania would all be the next most likely pickups. Finally, Minnesota, Michigan, Wisconsin, and maybe New Mexico could be picked up.
I'd say between three and thirteen is the range, depending upon popularity and a possible rally around the flag effect.