On Pennsylvania Primary Day Obama Widens National Lead in Gallup Poll, Clinton Seen As Negative

The most recent USA Today/Gallup poll finds Barack Obama with a 10 percentage point lead over Hillary Clinton nationally, 50% to 40%. That's up 3 percent from last month. Key findings:

Efforts by Clinton and John McCain ... to characterize Obama as elitist for his remarks at a San Francisco fundraiser seem to have failed. Seven of 10 say Obama "respects working-class Americans" rather than looks down on them — a slightly more positive reading than that for McCain or Clinton.

Democrats are divided, too, about whether the contest has become too negative. Among the half who say it has, 43% blame Clinton, 3% blame Obama.