Basing this on his personality, folks have basically said, "I'm so shallow, I don't care what he stands for, I just don't like him so I'll sit it out and pout."
Beyond this, are other things. Hillary Clinton is a criminal. People have died, many of them. She is a vile woman and everyone knows it. She may even be a traitor.
Stack this up against Trump, not likeable but with a fantastic platform, and not a criminal or traitor.
He is hated the most? Not buying that at all.