Are the majority of King's books set in Maine?

Yes.

He lives in Bangor (sometimes). I met and talked to him, shortly after his near-brush with death (a van hit and nearly killed him), at a local movie theatre.

He was very nice. I must admit, I was a bit starstruck. But I knew when to stop talking and leave him alone so he could enjoy the movie.

He and I were there to see the same movie, American Psycho, if you were wondering.

I don't know what he's doing these days, I haven't followed the release of his most recent books. But I have a soft spot for Cujo (the book and the movie).

BTW, Derry and Castle Rock are fictional, just like Cabot Cove from Murder, She Wrote.

Yes, I am a native Mainer, and I love lobster and steamers, and I'm proud of it! :-)

In the Dead Zone, Stephen King gave us Greg Stillson, a corrupt businessman who went into politics. Johnny Smith (the hero of the novel), saw a future in which Stillson became President of the United States (and started a nuclear war).

Of course, that could never happen in real life, a corrupt businessman becoming POTUS.

Oh wait...

In the Dead Zone, Johnny manages to change the future and prevent Stillson becoming President. Why couldn't something like that have happened with Trump?

Doc Brown. the Doctor and Bill and Ted tried and failed

Where was Johnny Smith when we needed him?