CNN is reporting that Hillary Clinton's lead in Pennsylvania has narrowed slightly. A new Quinnipiac poll shows Clinton leading Barack Obama 50 percent to 41 percent among likely Democratic voters, CNN's Political Ticker blog says. Pennsylvanians were polled March 24 through 31 - many of them before Pennsylvania Senator Bob Casey's endorsement of Barack Obama. A similar poll taken two weeks ago showed Clinton leading 53 percent to 41 percent, CNN says.