The problem is that he's a useful idiot for the Republicans in Congress right now. He gave them an Antonin Scalia wanna-be Supreme Court nominee, an EPA leader who hates the EPA, an Attorney General who will look the other way while they take away minority voting rights, etc. So long as they get to push their agenda, they're willing to sell their souls and put up with this shit.
My father bet my mother $100 that he would make it through all four years, and even now he doesn't think the Republicans will turn on him. Sadly, I think this is possible unless undeniable proof that he's compromised comes out, like actually finding that tape of the hookers pissing on the bed, or his tax returns. Or they lose badly in the next midterms. And like PC said, even if that happens, we then have a religious wacko president who actually knows what he's doing in Pence.