Democrats are going to have to think really carefully about how they deploy Barack Obama for campaigning this fall. Polls we've conducted nationally and in several different states over the last few weeks have found that a candidate being endorsed by Obama is much more likely to elicit a negative response from Republican voters than a positive one from Democrats.
PPP's most recent national survey found that while Obama had a positive approval rating at 48/47, only 33% of voters were more likely to vote for a candidate endorsed by him while 48% said support from Obama would make them less likely to vote for someone. That's because only 64% of voters who approve of the President say his endorsement would make them more inclined to vote for a candidate, but 91% who disapprove say Obama's support makes it less likely they would vote for one of his preferred candidates.
To put into perspective the perils of having Obama out on the campaign trail, consider the numbers in his home state of Illinois. Even there just 26% of voters say they'd be more inclined to back an Obama endorsed candidate while 40% say his support would be more likely to turn them against a candidate. It's another example where the intensity of feeling about Obama is much stronger on the GOP side- 80% of Republicans say they're less likely to vote for someone with the President's support while only 49% of Democrats say they're more likely to. If Obama's support isn't a net positive in Illinois it's hard to know where he should be deployed.
Whether Cal Cunningham or Elaine Marshall wins the Democratic Senate runoff in North Carolina next week neither is likely to get much benefit from Obama campaigning for them. 47% of voters in the state say they'd be less inclined to vote for someone he supported to only 30% who say his support would have a positive impact on their vote.