or Bob Casey Jr., it was one of the good days in his campaign to send Sen. Rick Santorum (R-Pa.) into political obscurity. Morning brought word of a new poll showing him with a 12-point lead over Santorum, who is the third most powerful Republican in the Senate, and evening brought an adoring audience to a fundraiser here in a private home, where Casey said with growing confidence, "I really believe this race is about America."

His voice, in contrast to the high-pitched, battle-ready aggressiveness that is in Santorum's, was polite as he criticized his opponent and President Bush, touched upon his Catholic upbringing and discussed his work as a Jesuit volunteer in inner-city Philadelphia. "In the life of a middle-class family, things are not going all that well," he said several weeks ago to the middle-class crowd, and as he went on, his quiet words blended with the cricket chirps coming through the open windows.

When Casey was done talking, the next sounds included scribbling pens and checks being torn out of checkbooks because of what Democrats say this race means: A Casey victory would not only topple one of America's best-known conservatives but would also enhance the Democrats' prospects of winning control of the Senate.

The Democrats need to pick up six seats to take control of the Senate, and Pennsylvania has become one of their best hopes. Emboldened by polls showing widespread discontent with the GOP-controlled Congress, Democrats vow a fundamental reordering of domestic and foreign policy if their party sweeps to victory in the Senate and House on Nov. 7.