On the Internet Watch KYW-TV video from this morning's radio debate in Philadelphia See WPVI-TV's Web site for coverage of tonight's debate at 7 p.m.

PHILADELPHIA -- Sen. Rick Santorum defended his 2005 visit to the family of Terri Schiavo while Bob Casey once again rebutted criticism of his work ethic and campaign schedule as drive-time commuters heard the first of today's two debates this morning in the home stretch of their campaign for the U.S. Senate.

The candidates appeared to have gone easy on the morning caffeine ration as the tone of the "Breakfast With the Candidates'' conversation in KYW Radio's Independence Square studios was decidedly more civil than their last encounter in Pittsburgh last week.

Both reaffirmed their support for the Bush administration's warrantless wiretap program. They agreed that all options should be on the table to discourage North Korea's nuclear ambitions, but, having said that, neither offered a clear road map of where the United States should go beyond the United Nations resolution of censure against the Pyongyang regime.

The rivals also traded familiar charges. Mr. Santorum accused the Democrat of avoiding specifics on issues, while Mr. Casey portrayed the incumbent as a rubber stamp for the Bush administration.

The exchanges came as the Santorum campaign released fund-raising figures showing that the incumbent's once vast fund-raising advantage had largely dissipated. Mr. Santorum fell behind Mr. Casey's fund-raising pace in the quarter than ended Sept. 30 and, while he has raised far more money in the campaign overall, the Republican headed into the last five weeks of their battle with slightly less remaining cash then his challenger.

That represented a sharp reversal in a nearly two-year battle in which the incumbent had held a consistent financial advantage. The third quarter report to the Federal Election Commission suggested that the Republican outspent Mr. Casey by a wide margin through the summer and early fall without appreciably closing the gap between them in public opinion surveys.

In response to the first question from one of the KYW panelists, Mr. Santorum said he had no second thoughts about his decision to visit the family of the Terri Schiavo, the late Florida woman whose feeding tube was disconnected after a legal battle in which Congress stepped in to give special jurisdiction to the federal courts in an issue that had been under a state review.

"I went there to pray with the family . . . and I'm not ashamed of having done that,'' Mr. Santorum said, noting that Ms. Schiavo's parents were his Pennsylvania constituents. Mr. Casey, who like Mr. Santorum, is a pro-life Roman Catholic, repeated his position that he would have "erred on the side of life," in the case. But, repeating his criticism of the Santorum visit, he said, "The last thing that site needed was a politician from Washington."

The candidates also repeated their difference on the Plan B morning-after pill. Mr. Santorum restated his opposition to over-the-counter sales of the pill, maintaining that in some circumstances it was tantamount to an abortion.

Emphasizing each syllable, Mr. Casey insisted that, on the contrary, the pill was "con-tra-ception,'' and he said that the scientific consensus supported that view.

Mr. Santorum pressed the Democrat to document that claim and said, "I don't know any organization that says this is not an abortifacient at times," Mr. Santorum said.

"Are you a scientist, too?" Mr. Casey shot back, although he acknowledged that he could not immediately cite a specific source for his conclusion.

It was one of several moments when Mr. Santorum, as he had Thursday in Pittsburgh, tried to turn the debate into a snap quiz, posing questions in hopes of demonstrating the Democrat's lack of familiarity with issues. At another point, he turned to Mr. Casey and asked him how far Chinese oil rigs were from U.S. shores.

"Tell us, Rick. You know everything," Mr. Casey replied. The Democrat bristled when Mr. Santorum returned to a frequent critical theme, his contention that Mr. Casey does not work hard, either in his state position or as a campaigner.

"I do my job; I show up for work," Mr. Santorum said as he pressed the Democrat on his attendance at his Harrisburg office.

"Everybody works hard Rick . . . in this campaign it's been very clear you've worked hard for the wrong people," Mr. Casey replied, suggesting that the Republican was beholden to oil and pharmaceutical interests.

"There's no transparency in your campaign," Mr. Santorum replied. "I've been fully accountable to the people."

"This lecturing of me . . . is ridiculous, and he knows it,'' Mr. Casey insisted. Mr. Casey renewed his own standard attack against the Republican, saying that he voted with the Bush administration "98 percent of the time."

Attempting to depict himself as an independent voice, Mr. Santorum cited a variety of issues on which he'd worked with senators across the aisle and he noted that he had worked against the Bush administration in his early championing of a tougher line against Iran.

In response to another question, Mr. Casey said that while he opposed gay marriage, he also opposed a proposed constitutional amendment banning it. He said it was an effort to politicize the issue.

The radio debate was broadcast on KYW radio in Philadelphia and KDKA radio in Pittsburgh. Tonight's televised debate, the last of the campaign under current plans, will be taped at the nearby Constitution Center and broadcast live locally.

The Pennsylvania Cable News network is to rebroadcast it at 8 p.m.

The FEC report, which covered the campaign's financial workings from June 30 to Sept. 30, showed that the Republican had raised approximately $3.5 million in direct contributions and another $200,000 in transfers from fund-raising committees. That trailed Mr. Casey's $4.13 million in receipts.

Mr. Casey had slightly more cash on hand at the end of the quarter, $3.7 million to $3.6 million, after a summer in which Mr. Santorum's dominance of the airwaves neither boosted his support in the consensus of polls nor made a significant dent in the Democrat's standing.

More details in tomorrow's Pittsburgh Post-Gazette.