A recent Civitas poll has Governor Pat McCrory still head of Roy Cooper, despite McCrory having a much higher  job performance disapproval percentage:

Now, please tell me whether you approve or disapprove of the job that Pat McCrory is doing as Governor?

Total Approve 53% Total Disapprove 39%

Now, please tell me whether you approve or disapprove of the job that Roy Cooper is doing as Attorney General?

Total Approve 49% Total Disapprove 15%

The poll conducted was of 600 registered voters and overall results were 41% for McCrory, 37 % for Cooper, 20% Undecided. Here is how the related question was phrased:

If the election for North Carolina Governor were being held today, for whom would you vote if the candidates were: (ROTATE) Pat McCrory, the Republican, and Roy Cooper, the Democrat?

20% undecided is pretty big.