Here is a breakdown from the NYTMES
Barack Obama won a razor-thin victory over Hillary Rodham Clinton in the Democratic primaries seven years ago in large part because black voters supported Mr. Obama by a 5-to-1 margin. Without their support, he would have lost, and lost big — probably by more than 20 points in the national popular vote.
As a result, many have framed Mr. Sanders’s challenge in racial terms. But his challenge in getting the support of nonwhite voters is not simply a problem of race. It’s primarily a problem with moderate and less educated Democrats, regardless of race, which disproportionately affects his support among nonwhite voters. His challenge among black voters may be no greater than his challenge among ideologically and demographically similar white voters.Meet the Press had a more straight forward infographic in this video.
The Democrats have spent decades dividing the country by age, race, income, religion and sexual preference so how can they run a campaign in 2016 with only old, white, rich progressives as the only choice to lead the party?