I wouldn't be surprised if Trump ramps up his maniacal behavior in the hopes that the Republicans take him out of the race. I've always had the sneaking suspicion that he was in it for the notoriety and press coverage rather than actually being a candidate.
Goldwater was a bigoted SOB but he did want to be president. Trump seems to be putting on yet another show. At some point the curtain will fall.

"The liberals can understand everything but people who don't understand them."
Lenny Bruce

"The cleverest of all, in my opinion, is the man who calls himself a fool at least once a month."
Dostoevsky