Republican-turned-Democratic Senator Arlen Specter trails potential GOP challenger Pat Toomey by five points in an early look at Pennsylvania's 2010 Senate race. But another Democrat, Joe Sestak, runs dead-even with the likely Republican candidate.

The latest Rasmussen Reports telephone survey of Pennsylvania voters shows 45% would vote for Toomey if the election were held today. Forty percent (40%) would vote for Specter, while six percent (6%) prefer a third option. Nine percent (9%) are undecided.

If Sestak wins the Democratic nomination, however, the race is a toss-up: 38% for Sestak and 37% for Toomey. In August, Sestak trailed Specter by 13 points in the race for the nomination. Rasmussen Reports will release new numbers in the Specter-Sestak race tomorrow at 7 am EDT.

In August, Toomey led Specter by 12 points. But that poll was taken at the height of the town hall protests when Specter endured some of the roughest treatment of any incumbent.

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Forty-six percent (46%) of Pennsylvania voters have a favorable opinion of Specter while 52% offer an unfavorable assessment of the longtime GOP senator who became a Democrat in April rather than face Toomey in a party primary. Those numbers are a few points better than they were in August.

Just 17% have a Very Favorable opinion of Specter while 37% hold a Very Unfavorable view. The comparable numbers for Toomey are 14% Very Favorable and nine percent (9%) Very Unfavorable. Sestak earns Very Favorable reviews from 10% and Very Unfavorable assessments from 11%.

Specter has found himself front and center in the health care debate. In August, just 42% of Pennsylvania voters favored the plan working its way through Congress. Since that time, national support for the congressional health care reform has increased a few points, but the numbers are broadly similar to August.

In Pennsylvania, voters are evenly divided over the creation of a government-sponsored non-profit health insurance option. However, if the so-called "public option" encouraged companies to drop private health insurance coverage for their workers, just 29% favor the plan, and 63% are opposed.

Specter, a longtime GOP senator, switched parties and became a Democrat in April just after a Rasmussen Reports poll in the state showed him trailing Toomey by 21 points in a likely Republican Senate Primary match-up. Specter's team initially dismissed the poll but later acknowledged that one of the reasons he changed parties was a fear that he might lose his own party's nomination.

Particularly damaging to Specter among Pennsylvania Republicans was his vote for President Obama's economic stimulus plan, one of only three cast by Republicans for it.

Eighty percent (80%) of Republican voters now favor Toomey in a match-up with Specter while the incumbent senator draws just 65% of the Democratic vote.

As part of the effort to coax Specter into switching parties to move Democrats closer to a filibuster-proof majority in the Senate, both the president and Pennsylvania's Democratic governor, Edward Rendell, endorsed Specter as the party's Senate nominee in 2010. They also promised to campaign for him. Sestak, angry like many Democrats in the state about a longtime Republican suddenly becoming the Democratic candidate for Senate, is challenging Specter for the nomination over the objections of his party's leadership.

Just 37% of Pennsylvania voters now approve of Rendell's job performance, down from 39% in August.

Fifty-one percent (51%) approve of Obama's job performance, a figure that is unchanged over the past couple of months. Nationally, a month-by-month review of the president's ratings shows that perceptions of Obama stabilized in September. His national numbers are updated daily in the Rasmussen Reports Presidential Tracking Poll.

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