I'm not sure how much to speculate on the impact of this all until the results are more locked down. But if the current results hold, it's one of the more confusing scenarios. It probably helps Sanders more than hurts him, but you could argue it either way. No matter what, he's still a pretty heavy favorite in New Hampshire, though. It will very likely help Buttigieg, but he has a LONG way to climb in polls nationally. It's not bad for Warren! It is bad for Biden, obviously, but an unambiguous Sanders win would probably have been worse for him. So it yields a mess overall, where each of the next three states matter quite a bit and there's a reasonably high risk of no majority/a contested convention. If you had to be one person, it would probably be Sanders.
By Nate Silver