I don't usually comment on polls, but it may be pertinent that
In 2008, Obama won 35 percent of the white vote in NC, while winning NC
This poll shows him at 37 percent of the white vote
In 2008, blacks were 23 percent of the electorate and voted 95 percent Obama
This poll has blacks at 21 percent of the electorate and 66 percent Obama (30 percent Romney)
The result is entirely the result of nearly one of three NC blacks deciding to switch to Romney.
SUSA always has screwy cross tabs though. I think this is an outlier, and I'll just leave it at that. Also SUSA does tend to be pretty volatile but usually ends up getting excellent results in their last poll.
