I think that for a lot of people, it's very hard to admit a mistake. And for people who were legitimately torn between Clinton and Trump (a position I will never understand, but whatever), they went in on Trump and are waiting to see what he will do.
A lot of people know that Trump is a bad guy, and still voted for him anyway. So everything that's happened so far? Not too surprising. He's a shit. But they expect him to deliver jobs and "be different". Unfortunately for them, the worst is probably yet to come. Starting with the AHCA.
That's all it would take to change the outcome.. let's revote!
The more interesting question would be how many sat home because they thought Hillary would win that would now get off their ass..?
This is probably a better question. My guess is that the younger voters who voted Johnson/Stein/didn't vote might switch to Hillary if we had to do a revote. Or not. Again -- it's hard to admit you were wrong. And if you accuse someone of being wrong, people tend to dig their heels in.