Look, we all know the demographics of the Democratic vote in NC and thus it is impossible for Hillary to win the state. He'll get 90% of a block of probably 35% of the total vote that will be black. Just do the math. Has Hillary gained ground among whites? I think any objective pundit looking at the recent polling would say absolutey that she has. She'll probably get as high as the low 60s max but we can all do math and know even that won't be near enough.
The scary thing for Democrats has been his performance among whites since Wisconsin. It's the reason he'll lose Indiana or any other primary state east of the Mississippi with less than 15% of the vote that is black. He's struggled with whites since Wisconsin. He's not even polling like he once was with white independents and that was part of his early primary coalition. This isn't a good trend for a candidate who has had the advantage of unlimited political funding in state after state.
Since Wisconsin we've had the following primary states:
-Texas
-Ohio
-Rhode Island
-Vermont
-Mississippi
-Pennsylvania
Now it's not difficult to see that whites in those states aren't exactly as favorable to Obama as whites in Wisconsin or many of the other states before it, except Vermont which Obama won in a walk. I've yet to see any actual evidence that the white vote has been drifting from Obama rather than just that the nature of the states up has changed.