Lyndon Johnson.
He messed up the Vietnam war so bad he didnt run for a second term.
LBJ was not removed from the ticket.
LBJ made lots of money for his military industrial complex buddies—the Vietnam War proceeded according to plan.
You may find this article interesting:
https://historynewsnetwork.org/article/166300
while that is partly true...Johnsons main reason was that his health was just awful.