While PPP, Gallup, and 2008 exit polls show disparate party identification breakdowns for most states in the country, the one where all three organizations converge is North Carolina with a finding that there are 11% more voters who identify themselves as Democrats than Republicans in the state. A full discussion of the party id issue here.
In 2004 exit polls actually showed a 1% Republican party identification advantage in the state, so this is quite a shift over the last four years.
Based on the current registration numbers in the state Democrats have a 14 point advantage, with 46% of voters in the state registered as Democrats and 32% as Republicans. The reason the identification advantage is narrower is that many voters who have been registered as Democrats since the 60s or 70s may actually be more likely to vote Republican now, particularly at the federal level, but have not bothered changing their official registration.