Clinton won the Democratic primary in New York on Tuesday by what looks to be about a 15 percentage point margin. While that generally matches pre-election polls, it is a devastating result for the Sanders campaign. The outcome almost certainly ensures that Clinton will beat Sanders in the elected delegate count after the final Democratic votes are counted in June.

Clinton entered the night with an elected delegate lead of about 205. That means, of course, that Sanders needs to catch-up. In order to do so, he has to win states with big delegate totals because of the proportional allocation rules that Democrats use in their primaries. Late last month, Nate calculated that Sanders needed to win New York by about 9 pledged delegates to remain on track for the nomination. Instead, Sanders lost the state by about 30 delegates or more. That’s a swing of about 40 delegates or more. To give you an idea of how big of a swing that is, that’s about double the total available delegates in Montana, which is expected to be a strong state for Sanders.

Sanders’s loss in New York means that he needs to do even better in upcoming contests than we originally thought to have any shot at winning more elected delegates than Clinton. More specifically, he’ll need somewhere in the area of 59 percent of the remaining elected delegates to eliminate his deficit to Clinton — he needed 57 percent before the night began. That means that he needs to win a state like Pennsylvania by closer to 10 percentage points instead of the 7 percentage points Nate originally calculated. (Sanders is behind in the Pennsylvania polling average by 14 percentage points.)

Indeed, the math just doesn’t look like it’s on Sanders’s side in upcoming contests. Besides Pennsylvania, he’s behind in all three of the other states with the biggest delegate prizes left on the calendar. He’s down 23 percentage points in Maryland — we originally estimated a 9-point Sanders loss would signal he was “on track.” Sanders trails Clinton by 9 points in New Jersey, which he originally needed to win by 6 points. Most importantly, he’s trailing by 13 percentage points in California, where he needed to win by 15 points.

http://fivethirtyeight.com/live-blog/new-york-primary-presidential-election-2016/