Bob Dole, lol. Funny you should mention him:
He was doing only what he wanted to do now. The day before, he had quit campaigning, again after only two speeches, in mid afternoon, in order to beat the curfew at National Airport, in Washington, to which he insisted on returning so that he could spend the night in his own bed. Every day, the campaign provided Dole with a positive, issues-oriented speech. The advance texts of these speeches were dutifully put up on the TelePrompTer and handed out to reporters. Sometimes Dole delivered the speeches, but more often he didn't. He said, it seemed, whatever he pleased, whatever popped into his mind. What pleased him most was to rail against Clinton, so that was what Dole was going to do, no matter what his advisers said... Dole's campaign for President was, in a sense, always a protest campaign: Dole's protest against everything--the culture of politics, the culture of his country, the values of a nation that appreciated a man like. Clinton more than a man like Dole...
from here
Trump's candidacy has always been a protest against anyone he feels has slighted him in some way. And now that he has the nomination, he continues to attack the very party who put him there.
This is the end result of the Southern Strategy employed by the GOP now for decades. Trump, the small handed vulgarian, is the fruit of that toxic seed. It was always going to end poorly.
And I'll just add, for as weak a candidate as Hilary is, she's the front of one of the most organized and effective political campaign machines in U.S. history. I'm talking from the street level all the way to the top. It got Obama elected twice and is well on its way to getting Hilary into the White House.