Barack Obama has a slight lead in Ohio and Florida, while he's well ahead of John McCain in Pennsylvania, a new Quinnipiac poll of swing states released Thursday found.

"Florida and Ohio are too close to call," the polling firm said.

Obama, the presumptive Democratic presidential nominee, is up 46-44 in Florida, down slightly from his lead last month. In Ohio, Obaham is also up 46-44, also down.

And in Pennsylvania, Obama leads 49-42, down from his 12 percentage point advantage over McCain, the presumptive Republican nominee, in the last poll.

The three states are crucial to both candidates' chances. No president since 1960 has won without taking two of the three states.

To read the poll results: http://www.quinnipiac.edu/x2882.xml?ReleaseID=1196