Surprises happen. Years ago I lived in Maryland, a very democratic state. Never heard anyone talk about any republican candidates. Really, not a word. Election day comes and what do you know, state went republican. Even half the people I worked with voted republican, but only admitted it after the election.
It happens. Those blue states you’ve mention have/have had republican governors, senators, state officials.
I’m very interested in politics. I’d take the time to figure out how to vote where I live. I did register at college when I lived there, at grad school, whenever I move. My kids? One cares, but will probably absentee vote because we live in a swing state and her school state is not budging no matter how many students vote. The other one is in a swing state, but she doesn’t care about politics and will not make any effort to get special IDs (although I don’t think it would be hard since she lives in a house) or stand in line for hours. Kids these days!