I like Alaphilippe on form (and I just like his style), but I think he'll be marked by everyone. It's very difficult for a favourite to win at MSR. If he does win, I think it will be on the descent of the Poggio, where he could shake off a small group, although not if it's still a very large peleton by then - he's got crazy descending skills, as well as being able to climb explosively and great sprinting speed. He's a proper all-rounder.
Dark horse for me is someone like John Degenkolb, who hasn't been on the radar all season, but has been waiting for this. But who knows?