Will that scenario happen in all HOR races? No, but the R will remain in the majority in the HOR.
Demograhics is destiny. In both Virginia and the US in general, years more of massive inflows of foreign nationals and multiculturalism on steroids is tipping the country further and further to the left. Trump is trying, but the Congress is hamstringing him at every turn. The Mueller endless investigation is also a weapon of the Uniparty to cripple him.