Democratic Sen. Bob Casey has cultivated the kind of voting record in the Senate that earns him very few enemies. It also makes it difficult to run against him. Still, Republicans nominee Tom Smith, a self-made wealthy businessman who has not hesitated to put his own money into the race, has aired a barrage of television ads and has succeeded in denting Casey’s armor. Polling shows that Smith has pulled within single digits of the incumbent, who now seems more focused on the race and has started to attack Smith as a “Tea Party extremist” in television ads. While Casey maintains an advantage in the race, it is now worth watching. It is in the Lean Democratic column.

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