Fear-based voting is extremely popular. In 2008, the argument was that people should vote for Obama because John McCain is old and will die, leaving Sarah Palin who is apparently stupid or something. In 2012, the driver was that Obama’s first debate performance was so bad, he could lose the election, so you’d better go to the polls. The fear doesn’t have to be real, of course. McCain is still alive and cancer-free. Sarah Palin was one of the first to see the potential for a Trump candidacy.
There was , however, a little fear this year. In February, Antonin Scalia dies while on the Supreme Court. As the most conservative member of the Court, his replacement would have been a reversal. The Republican made the Hail Mary bet of blocking an appointment until after the election, probably thinking Jeb or Kasich would be the Republican nominee.
When Trump became the nominee, one of the strongest arguments for a conservative to vote for him was the direction of the Court. Never Trumpers had the ineffective response that Trump might pick a less conservative Justice than a “real” Republican. Of course, Clinton would have picked another Ginsburg.
My contrarian argument is that Trump was able to collect both the disaffected blue-collar populist vote and the support of mainstream Republicans because Hillary controlling SCOTUS was too scary a prospect. Ironically, Scalia’s death may have been the best thing for the Trump campaign and the GOP.