I keep forgetting about Tim Kaine. I think it's pretty clear that either (a) Virginia is now a very Democratic state or (b) Kaine is a popular Senator who propelled Clinton to victory in Virginia or (c) Trump is a bad fit for Virginia. Either way, Kaine has very little to worry about.
The first one.
Running mates don't "propel" candidates to victory anywhere.
Trump was an exceptionally bad candidate for Virginia, but it has also gotten to a point where Generic R is no longer electable statewide in VA. The Republicans have to run a really exceptional candidate in order to win there.