Senator Arlen Specter leads Congressman Joe Sestak by 19 percentage points in an early look at the 2010 Democratic Senatorial Primary in Pennsylvania. The first Rasmussen Reports telephone survey of the race shows Specter attracting 51% of the vote while Sestak earns 32%.

Not surprisingly, Specter, a senator for nearly 30 years, is much better known than Sestak, a retired Navy admiral and second-term congressman from the Philadelphia suburbs.

Thirty-five percent (35%) of likely Democratic Primary voters have a very favorable opinion of the incumbent senator, who recently switched parties to improve his chances for reelection. Only 18% say the same for Sestak.

The number with a very unfavorable view is virtually identical: 10% for Specter and nine percent (9%) for Sestak.

Tomorrow (Thursday), Rasmussen Reports will release general election match-ups featuring Specter and Sestak against the Republicans' likely Senate nominee, former Congressman Pat Toomey.

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Specter, a Republican senator since 1981, has always had a difficult relationship with the GOP base. Earlier this year, he was one of only three Senate Republicans to vote for President Obama’s economic stimulus package. That vote clearly hurt him back in the Keystone State where a majority of Republicans said they were less likely to vote for him because of his stimulus support.

Toomey, who Specter narrowly defeated in the 2004 state Republican Primary, announced his plans to challenge the incumbent again next year. Just after subsequent polling showed Specter trailing Toomey by 21 points in a GOP Primary match-up, the senator switched parties and became a Democrat.

While Specter was coaxed by senior Democrats to switch with the promise that he would be the party's Senate nominee in 2010, Sestak is bucking his own party leaders to mount a primary challenge. Both Obama and Pennsylvania Governor Edward Rendell have already endorsed Specter and pledged to campaign for him.

Looking ahead to 2010, it is not clear how Specter’s vote on the stimulus bill will impact his bid for reelection. Just 31% of voters nationwide believe the stimulus plan has helped the economy while 27% say it has hurt. A solid plurality now say that all remaining stimulus spending should be cancelled. However, opinions of the economy and the stimulus package may be substantially different in 2010.

Specter leads Sestak among men and women, young and old. He has a substantial lead among African-American voters, but the two candidates are essentially even among white voters in a Democratic Primary match-up.

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