There are a lot of numbers in this analysis. But the overall takeaway is that Sanders may face a significant challenge securing the nomination for the Democratic party.
https://fivethirtyeight.com/features/bernie-sanders-can-win-but-he-isnt-polling-like-a-favorite/
https://fivethirtyeight.com/features/bernie-sanders-can-win-but-he-isnt-polling-like-a-favorite/