I wonder if some of the disappointment on the part of Sanders people for black support of Clinton is just simply this: blacks are disproportionately poor, compared with whites and Asians, therefore they should be a potential core constituency for the candidate who is most in favor of changing the current socio-economic system, Sanders.
I read a really interesting article about how because of the broad systemic issues AA and Latinos face, they're less likely to invest in idealism and focus on pragmatism.
Another factor to consider, especially in red states in the South, many believe that a Democratic president/administration is their only hope against an otherwise solidly Republican state government and legislature, so electability plays a bigger role in their decision.
