I actually didn't pick up on the religious implications of this Jack Conway ad attacking Rand Paul before Jonathan Chait wrote a post about it, but I'm sort of surprised to see liberals latch on to it as particularly reprehensible in comparison to the other ads this cycle. What originally bothered me about the ad was that it exaggerated unimportant but salacious details of Paul's life from decades ago and tried to turn them into a campaign issue -- watch how this fades as the first generation of people with their college lives preserved on Facebook start running for office.
Still, it's hard to see it as the "ugliest, most illiberal political ad of the year," as Chait and Ezra Klein refer to it. How about this ad from Sharron Angle, attacking "illegals" and contrasting what are meant to be scary looking Latino migrants with happy, smiling white college graduates as it attacks the DREAM Act? Or this ad run by North Carolina Republican Congressional Candidate Renee Ellmers calling the proposed Islamic center near Ground Zero a "victory for the terrorists"? Or David Vitter's ad showing bunch of stereotypical illegal immigrants sneaking through a fence, only to be greeted by a sign that says "bievenidos a los USA"? Maybe this one attacking Pennsylvania Democrat Joe Sestak for "raising money" for a "front-group for Hamas"? There aren't quite as many examples from the left, but if you wanted to really go for it, there's always "Taliban Dan," or Rep. Zack Space's weird attack on China.
I could really continue. There's a part of me that suspects this Conway ad is a bigger deal, because while few political reporters can imagine being a Muslim or an unauthorized immigrant, a lot of us can imagine being unfairly attacked for something stupid we said in college.
Meanwhile, I'd add that I disagree with Theda Skocpol that playing "hardball" necessarily means "lying about your opponent." Paul's stances on various matters are wrong and unpopular enough that his personal life needn't be brought into it, certainly not to the point of suggesting that "mocking Christianity" is a disqualification from public office. But it's not as though ads portraying all Muslims as terrorists don't imply the same religious test while at the same time attacking an unpopular religious minority -- are we supposed to believe the same people who buy Ellmers' characterization or the Park51 project would suddenly get all ACLU if someone like Keith Ellison decided to run for office in that same district?