Just for fun let's compare the trend lines for the Republican presidential race in North Carolina and nationwide side-by-side. The hometown factor for John Edwards renders similar comparisons for the Democrats meaningless.
Nation (from pollster.com)
I tried to match the colors for the candidates' trend lines. The beginning of the NC trend corresponds with the blue vertical line on the nationwide graph that signifies the beginning of 2007.
As you can see, Fred Thompson is doing much better in North Carolina than he is nationally. Also, Rudy Giuliani is dipping nationally and in North Carolina. Same goes for McCain, who is falling off the charts. Nationally, Romney has not quite reached McCain's level, but he has in NC.