Presumably a tie for Gillespie with a 2016 electorate transfers to a narrow lead in an off-year electorate, and this is before popular Obama leaves office and unpopular Hillary is inaugurated. Decently likely Republican pickup here, I would say, unless the primary really goes off the rails.
I highly doubt the popularity of Hillary will matter at all in this race. McAullife is a mostly invisible governor, so there's not much for the GOP to rail on.
I think Northam will win 50-47 or something like that.