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Rand Paul, the Tea Party-backed Republican Senate candidate in Kentucky, said Monday he may boycott a final debate against Democratic opponent Jack Conway scheduled for next week, in frustration over ads Conway has run challenging Paul's adherence to Christian ideals.

"We haven't fully decided," Paul said after a press conference with a veterans backing his campaign, "but I'm not sure I'll appear in public with someone who is going to question my religion."

John Collins, a Conway campaign spokesman, said in a statement that Paul "ought to have the guts to keep his commitment to KET and explain his actions to the people of Kentucky." Public television station KET was to broadcast the final scheduled debate between Paul and Conway on October 25.

The uncertainty surrounding that event followed an unusually heated TV debate Sunday night, hosted by the University of Louisville, that saw Paul, a trained opthamologist, and Conway, the state attorney general, trade barbs about each other's character, integrity, and prior statements. Paul, at debate's end, refused to shake Conway's hand.

In televised ads prior to Sunday's debate, Conway - who trails in most statewide polls by an average of five percentage points - had urged Paul to provide details about a prank he allegedly took part in during his undergraduate days at Baylor University. According to GQ magazine, which first unveiled the charges in August, Paul and a classmate blindfolded and kidnapped a woman, demanded she smoke marijuana from a water bong, and later tried to force her to kneel before a god the two men identified as "Aqua Buddha." GQ kept the woman's identity anonymous and Paul has described the account as "ridiculous."

"The woman who you tied up said...that it was weird, [and] that she ended her friendship with you because of it," Conway told the debate audience Sunday night. "And I just don't think anyone should ever tie up a woman and ask her to kneel before a false idol." In the TV ads Conway had run, an announcer had gone further, saying: "Why was Rand Paul a member of a secret society that called the Holy Bible ‘a hoax,' that was banned for mocking Christianity and Christ? Why did Rand Paul once tie a woman up, tell her to bow down before a false idol, and say his god was 'Aqua Buddha'?"

Although Conway had not made the allegations a part of his opening statement, Paul seized on the ads and forced the issue into a primary role in the debate. "Jack, you should be ashamed of yourself," Paul said early on. "Have you no decency? Have you no shame?" When Conway accused Paul of failing to answer the questions raised in the ads, Paul snapped, to gasps from the audience: "Jack, you know how we know when you're lying? It's when your lips are moving, okay?...You're going to stand over there and accuse me of a crime from thirty years ago from some anonymous source? How ridiculous are you? You embarrass this race."

Numerous observers, including both neutral analysts and Democrats active in Kentucky politics, questioned the wisdom of the Conway campaign focusing so heavily on the GQ allegations. "When Conway began the personal attacks, I think it did take him off-message," University of Louisville political science professor Jasmine Farrier told Fox News. "He kept the negativity on a college prank that allegedly happened thirty years ago, rather than linking it explicitly to character, policy, and association issues which might put Rand Paul out of the mainstream for conservative Democrats and swing voters in Kentucky. That was the strategic error of the Conway campaign.

Farrier argued that Paul was keen to seize on the allegations because it enabled him both to question Conway's character in pressing them, and to skirt tougher questions on more substantive issues, like whether Paul believes in the constitutionality of Social Security and wants to pare back federal mining regulations.

"I think even among the Conway supporters [in the university audience], there was a measure of disappointment and a universal cringing effect that the two men engaged in that kind of back and forth," Farrier said.

A Kentucky Democrat who has helped run two successful statewide campaigns, and who supported Conway's primary opponent in the current election cycle, agreed the emphasis on the GQ charges worked to the Republican candidate's benefit. "This basically gives Paul a chance to do nothing but play the injured party and talk about his family values," said this operative. "If you run something like that, you better have your opponent dead to rights, not some 30-year-old college prank."

Another politico who has advised one of the two House Democrats seeking reelection in Kentucky this year told Fox News that Conway "is on his own" with the ad, and suggested it has deepened concerns about a possible "meltdown" by Conway that could serve as a drag on the rest of the Kentucky's Democratic slate. "This is exactly how Paul won the primary so big - [Republican Secretary of State Trey Grayson] went overboard on the attack and Paul was able to turn it around on him," said the second Kentucky Democrat.

Appearing on MSNBC Monday morning. Sen. Claire McCaskill (D-MO) called the ad "very dangerous" and said it verges "close to the line" of propriety. But McCaskill also accused Paul of being "thin skinned" for refusing to shake Conway's hand after the Sunday debate.

Fox's Chris Stirewalt contributed to this report.