No. History shows the process of demographic change is incredibly hard to stop short of nationwide genocide...and I'm quite sure we're not going down that road. Our young are increasingly accepting of people who don't look, act, or think as they do. Remember the old saying, "You can't go home again"? Same thing here - "You can't go back to the 1950's again." It no longer exists except on celluloid.
At most, the white supremacists are delaying the inevitable. It is true that given the chance, the Right would embrace an authoritarian government covered with a wisp of a fig leaf of democracy to imply legitimacy.
But I don't see that happening. If Trump were to somehow remain in the Oval for four more years, the civil unrest across the nation would make the last four years look like a walk in the park.
Our nation and democracy will survive, but I'm afraid our worldwide standing and reputation has suffered a wound from which it will never fully recover.