You've probably already heard the one about the Democratic candidate who questioned his Republican opponent's claims to Christian faith. Republicans are shocked, shocked that a Democrat would go after a member of Christ's party, as if everyone doesn't already know that Democrats would hate God if only they believed in Him. Even some liberals have hopped the outrage train. Democrats don't do religious attack ads, lest they give the impression that there are religious tests for office, or signal that voters care much about a candidate's faith.Here's the thumbnail: Democrat Jack Conway is running against Republican Rand Paul to represent Kentucky in the Senate. During Sunday night's debate, they traded barbs over an ad Conway is running that says Paul, who sought and obtained the endorsement of James Dobson after proving his prolife Christian mettle, belonged to a "secret society that called the Bible a hoax," a group that was "banned for mocking Christianity and Christ." The ad also says Paul "once tied a woman up," telling her to "bow down before a false idol and say his god was 'Aqua Buddha.'" During the debate, Paul went the "have you no decency, have you no shame?" route, and Conway flatly said, "You don't have the guts to stand by your positions."Some liberals echoed Paul's response. Jonathan Chait called the ad illiberal, lamenting its "sickening premise" for coming "perilously close to saying that non-belief in Christianity is a disqualification for public office." (Chait also helpfully reminds readers that Paul is a devotee of another, less Christian-friendly Rand.) Others find liberal opposition to the ad "prissy," and applaud Conway for hitting Paul where he's trying to live. Who's right? I suspect Chait is exaggerating the ad's implications. I'm with Mark Silk, whonotes that if a candidate is going to run on his Christian faith then his opponent is well within his rights to say "explain these things"--especially when these things entail membership in a group that called the Bible a hoax, and participating in a hazing prank that forced a presumably Christian woman to blaspheme. Mark concludes:

Democrats have tended to respond by saying, "But we're religious too." So because the religion card is being played by everyone, I'd say that if there's reason to question its face value, let the questioning go on.

Of course, this smoke might clear if Paul denied Conway's charges. But he hasn't, and, as Factcheck noted, he really can't. The only problem in Conway's ad, according to Factcheck, is the claim that Paul wants to end tax deductions for religious institutions. That, at least, is something Paul's campaign denies.For my part, this controversy is a tempest in a shave cup, and it distracts from what may truly be the worst political ad of the 2010 cycle, Illinois Governor Pat Quinn's attack on his Republican challenger Bill Brady: