I actually wanted to start a social network / organizing app. Around this. People essentially 'volunteer' to move where we need them to. But they actually would move for a few years. Maybe even stay there, permanently. As long as they live there, they can vote there.
Emphasis at first would be red states close to turning blue, or with large electoral college votes. Then maybe states needed for local change, could ask people to move to 'support' the changes needed. Like legalizing cannabis in Utah (we'd need a lot more blue for that to ever happen even via ballot initiative, it's a miracle we got medicinal).