It’s literally almost impossible at this point for the democrats to win the House of Representatives without massive gerrymandering in the deep blue states, a look at the county-by-county map of the 2024 election shows this clear as day.
The other problem that will arise in a few months is some of these incumbent Dems might get primaried and lose. The GOP should get itself positioned to help with a little subterfuge in this regard, because the challenger could damage or beat the incumbent, and then massively lose to the Republican.