I think the gerrymanders will actually hurt them. They are weakening strong republican districts to create a bunch of Trump +5 districts. If the elections in Virginia and New Jersey hold in the midterms, not only will Dems still hold those districts but can also take the seats Republicans weakened and actually gain seats. It's why you saw Kansas and Indiana abandon plans to gerrymander. On top of that, Republicans drove California to gerrymander.