He emerges from several days trailing Hillary in Gallup's national numbers to take a "statistically significant" five-point lead. Not what you'd necessarily expect post-Texas and Ohio. Maybe Hillary got such a media lift that the anti-media pendulum is swinging back yet again? (He also leads by 3.7 in the RCP national poll average, by the way.)
With most of the primary voting behind us national primary polls seemed irrelevant until recently. But now they're likely to have a real influence over superdelegates. Although probably not as significant as the head-to-heads against McCain, in which Obama also fares a few points better than Clinton (but which I would argue are a pretty suspect predictor at the moment).
(Thanks to prized reader KB)