Former Republican Rep. Pat Toomey has big leads over Sen. Arlen Specter and the other Democratic hopeful for Specter's seat, Rep. Joe Sestak, among the state's likely voters, according to a Franklin & Marshall College poll conducted Jan. 18-24.

Toomey leads Specter among that group, 45 percent to 31 percent, with 20 percent undecided, and Sestak by 41 percent to 19 percent with 37 percent undecided.

F&M cautions that at this point, "Pennsylvanians are still paying little attention to the primary races for governor and U.S. senator and that the candidates in those races remain largely unknown to the state's voters." Sixty-five percent say they don't know enough about Toomey to have an opinion of him and 76 percent say the same about Sestak.

The pollster says two factors will be key as the race develops: whether the Democrats can match the Republicans' enthusiasm and how much Toomey's numbers change as he becomes better known. Right now, 35 percent of registered Democrats say they are likely to go to the polls compared to 47 percent of Republicans.

Specter faces some formidable challenges. Forty-three percent see him unfavorably compared to 35 percent who regard him favorably, with 13 percent undecided and 9 percent saying they don't know. Only 34 percent of registered voters say he is doing a good or excellent job as senator and even fewer -- 29 percent -- say is doing a good enough job to be re-elected.

Thirty-nine percent say Specter's decision to switch parties made it much less or somewhat less likely they'd vote for him, 38 percent said it made no difference and 19 percent said it made it much more or somewhat more likely they'd support him.

Forty-two percent say his vote in favor of the health care legislation in the Senate made it much less or somewhat less likely they'd back him, 28 percent said it made them much more or somewhat more likely to vote for him and 23 percent said it made no difference.

As for the Democratic primary, Specter leads Sestak, 30 percent to 13 percent, among registered Democrats, with 7 percent undecided, and half those surveyed having not made up their minds.

The New York Times has an in-depth look today on Specter's uphill fight.

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