From what I understand (which is based on Clay Shirky's Twitter feed, make of that what you will) Bernie had zero appeal to black voters, who are an essential d

From what I understand (which is based on Clay Shirky's Twitter feed, make of that what you will) Bernie had zero appeal to black voters, who are an essential demographic for the Democrats. He was very popular in a young, white bubble, which is also important, but still a bubble.