According to IMDB, John Amos was in 13 episodes, and is still alive. But the "main" characters who were in 30+ episodes, seems like Ms. White is the last :sad:Ed Asner, who played Lou Grant on The Mary Tyler Moore Show and later the spin-off of the same name, died today. He was 91.
Asner also starred in Up. I think that Betty White is now the only main cast member of The Mary Tyler Moore Show who's still alive?