In a head-to-head fall matchup, U.S. Sen. Arlen Specter (D., Pa.) maintains a lead over Republican Pat Toomey, although the former Lehigh Valley congressman has gained ground, according to a poll released this morning.

Specter holds a 46-37, percent edge, Quinnipiac University found. That is down from a 53-33 percent margin Specter enjoyed in a May 4 poll by the Connecticut university.

"Sen. Arlen Specter's numbers have slipped since the controversy that followed his switch to the Democratic Party, but he's still better off than he would have been if he stayed a Republican and faced a tough primary challenge from former Rep. Pat Toomey," said Clay F. Richards, assistant director of the Quinnipiac's Polling Institute.

The survey shows that Specter and Toomey hold huge leads in head-to-head matchups with possible primary opponents: Specter is besting Democratic U.S. Rep. Joe Sestak 50-21, while Toomey is topping U.S. Rep. Jim Gerlach 38-10 percent.

The poll surveyed 1,191 state voters from May 20-26 and has a margin of error of 2.8 percent.

It also showed that Pennsylvanians are giving high approval ratings to President Obama (62-31), Gov. Rendell (54-37) and Sen. Robert P. Casey (56-21).

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