[cnn-photo-caption image= http://i2.cdn.turner.com/cnn/2009/images/07/22/art.specter0722.gi.jpg caption="A new poll out Wednesday has bad news for Sen. Specter's re-election bid."]
(CNN) - A new poll of Pennsylvania voters suggests that Sen. Arlen Specter's double-digit lead over Republican challenger Pat Toomey in his bid for re-election next year has disappeared.
Forty-five percent of people questioned in a Quinnipiac University survey released Wednesday say they'd back Specter if the 2010 election were held today, with 44 percent supporting Toomey. That's a dramatic change from early May, soon after Specter switched from the Republican to Democratic parties, when a Quinnipiac poll indicated Specter held a 20 point lead over Toomey.
By a 49 to 40 percent margin, the poll indicates that Specter does not deserve to be re-elected to a sixth term next year. And 47 percent approve of how Specter's handling his duties as senator, matching his lowest approval rating ever in Quinnipiac polling. Forty-six percent disapprove, the highest disapproval rating ever.
"Sen. Arlen Specter's 20-point lead over former Congressman Pat Toomey less than three months ago has virtually vanished," said Peter A. Brown, assistant director of the Quinnipiac University Polling Institute. "Voters see Sen. Specter much less favorably than they once did and are net negative about giving him a sixth term in the U.S. Senate."
The fiscally conservative Toomey is a former congressman and former head of the Club for Growth, a limited-government, anti-tax organization. Toomey nearly beat Specter in the 2004 GOP senate primary.
Toomey was leading Specter in polls of a hypothetical Republican Senate primary earlier this year, before Specter switched his party identity from Republican to Democrat. Specter said then the difficulty in winning the Republican primary was a factor in his decision to switch parties.
The survey indicates that Specter leads Rep. Joe Sestak 55 percent to 23 percent in a hypothetical Democratic primary matchup. Sestak, the two-term congressman from Pennsylvania's 7th District has said that he will challenge Sen. Arlen Specter for the Democratic Senate nomination next year.
Sestak just finished up a three-week tour of Pennsylvania's 67 counties, and it's possible he may have an official announcement regarding a Senate bid now that the tour is over.
Specter has the backing of President Barack Obama and Democratic leaders.
The Quinnipiac University poll was conducted July 14-19, with 1,173 Pennsylvania voters questioned by telephone. The survey's sampling error is plus or minus 2.9 percentage points.