"There is no mystery here. Except for people who have been hiding in caves or living in denial, it’s pretty widely understood that a substantial number of those voters — in Pennsylvania, Ohio, West Virginia and elsewhere — will not vote for a black candidate for president.
"Pennsylvanians themselves will tell you that racial attitudes in some parts of the state are, to be kind, less than enlightened. Gov. Ed Rendell, Hillary Clinton’s most powerful advocate in the state, put it bluntly last February: 'I think there are some whites who are probably not ready to vote for an African-American candidate.'”