Richard Burr's campaign would like to have you believe that his bad poll numbers are just a construct of liberal biased PPP. They even went and got a story written about it in Politico last summer.
I guess they're going to have to bash the highly nonpartisan Elon Poll now too. It finds today that only 24% of North Carolinians think that Burr deserves reelection, while 51% think it's time to give someone else a chance. Those are pretty devastating numbers.
I still think it's possible that this is going to be not exclusively an anti-Democratic year so much as an anti-incumbent year. That will still make for a tough cycle for Democrats since they account for most of the incumbents, but it also means you could see someone like Burr lose for reelection even as his party gains overall.