Incumbent Senator Arlen Specter trails former Congressman Pat Toomey by 21 points in an early look at Pennsylvania’s 2010 Republican Primary. Fifty-one percent (51%) of Republican voters statewide say they’d vote for Toomey while just 30% would support Specter.

Specter is viewed favorably by 42% of Pennsylvania Republicans and unfavorably by 55%, according to a new Rasmussen Reports telephone survey of voters in the state. Those are stunningly poor numbers for a long-term incumbent senator. Specter was first elected to the Senate in 1980.

Toomey, who served in the House from 1999 to 2005, earns positive reviews from 66% and negative comments from just 19%.

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Though Specter has been in the Senate for 28 years, he has struggled to maintain grassroots support within his own party during recent years. Six years ago, the incumbent barely survived a primary challenge and defeated the more conservative Toomey by just two points, 51% to 49%. He then went on to win the general election in 2004 by a 53% to 42% margin.

This time around, things could be even more challenging for Specter. He was one of only three Republicans in the Congress to vote for President Obama’s $787 billion stimulus plan. Fifty-eight percent (58%) of Pennsylvania Republicans said they were less likely to vote for Specter because of his support for the stimulus package.

In another sign that could be troubling for Specter, the current poll finds that 79% of Pennsylvania Republicans have a favorable opinion of the “Tea Party” protests against big government spending and higher taxes held across the nation last week. Thirty percent (30%) know someone personally who took part. Overall, 82% of Pennsylvania Republicans say that the federal government has too much money and too much power. Just four percent (4%) say it has too little.

Specter leads Toomey by just eight points among moderate Republicans statewide, but Toomey holds a solid advantage among conservative Republicans.

In 2004, Specter benefitted from the fact that the official Republican establishment strongly backed his candidacy against Toomey. Early indications are that he will not enjoy such support this time around. One reason may be that Pennsylvania has been trending more Democratic in recent years, and Specter has shown weakness in early general election polling match-ups.

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