Virtually the entire Republican apparatus will follow Trump sooner or later, because without the voters, they have no power. And those voters have revealed things about the nature of the party that many Republicans prefer to deny. Whatever abstract arguments for conservative policy — and these arguments exist, and a great many people subscribe to them earnestly — on the ground, Republican politics boils down to ethno-nationalistic passions ungoverned by reason. Once a figure has been accepted as a friendly member of their tribe, there is no level of absurdity to which he can stoop that would discredit him. And since reason cannot penetrate the crude tribalism that animates Republicans, it follows that nothing President Obama could have proposed on economic stimulus, health care, or deficits could have avoided the paroxysms of rage that faced him.
The paranoid mendacity of Joe McCarthy, the racial pandering of Barry Goldwater, Richard Nixon, and George Bush, the jingoism and anti-intellectualism of Ronald Reagan, George W. Bush, and Sarah Palin — all these forces have embodied the essence of American conservative politics as it is actually practiced (rather than as conservative intellectuals like to imagine it). Trump has finally turned that which was always there against itself.