Here’s the thing… Democrats could flip the House and increase their lead in the Senate easily. In fact, they could make their leads in both chambers practically insurmountable. All they’d have to do is have small numbers of Democratic voters in the large states move to states like Wyoming, the Dakotas, Idaho, etc. Have a few million people migrate from California, New York, and Illinois, and those deeply red states would instantly become bright blue.
The problem, however, is obvious: How do you convince someone living in New York to move to North Dakota?