PPP's Tom Jensen notes that Burr's approval rating is only 37%, with 40% disapproval. Another reference point for Burr's status as a weak incumbent is that his polling right now is similar or even worse than his fellow Republican Senator Elizabeth Dole was in 2008 -- and Dole went on to lose re-election in North Carolina by nine points.
Nevertheless, Jensen cautions:
It's good for Marshall and Cunningham that they're in a comparable or better position than Hagan at this point two years ago, but there's no guarantee the rest of this story will play itself out as it did in 2008. It's still shaping up as a strong election year for Republicans in North Carolina, and the turnout numbers from last week's primary suggested a lack of interest in this year's election among Democratic voters. Still it's becoming increasingly clear that Burr will not coast to victory this fall, and that regardless of who the Democratic nominee is this should be a very competitive race.