01/08/2012 04:23 pm ET Updated Mar 09, 2012

Why Some Attack Ads Work and Others Fail

With Rick Santorum emerging as the latest "anybody but Romney" flavor-of-the-month for Republican voters, it's inevitable that other GOP candidates will unleash a barrage of negative ads targeting the former Pennsylvania Senator. One of the first anti-Santorum ads, produced by a Ron Paul affiliated SuperPac, produces a few giggles -- a Santorum impersonator threatens to avenge his narrow Iowa loss by attacking places that start with "I" such as Ikea and IHOP -- but probably won't impact the election. In this context, it's interesting to look at the current negative ads and those of the past to see which ones work, which don't, and why.

Let's look at some other major negative ads first. A ubiquitous 2008 John McCain ad attacking Barack Obama as a "celebrity" who offered more flash than substance didn't stick either because former Harvard Law Review editor Obama isn't an empty suit. On the other hand, Mitt Romney's attacks on Newt Gingrich as a dishonest hypocrite with leanings towards the political left succeeded in pushing the former House Speaker out of the GOP primary's top ranks even though his overall record is more conservative than the former Massachusetts governors'. George W. Bush's followers, likewise, probably destroyed John Kerry's chances of winning the election with a series of "Swift Boat" ads that portrayed the decorated combat veteran as a preening coward. So did a television campaign (aided and abetted by relentless media coverage) that portrayed former Virginia Senator George Allen -- arguably the Senate's strongest supporter of historically black colleges -- as a bigot who uses obscure racial slurs like "maccaca" on the campaign trail.

So why do some negative attacks stick -- even when they're dishonest -- and others roll off even when they're largely accurate? I'd suggest that it has a lot to do with the way that effective attacks point to candidates' character flaws while ineffective ones simply try to make the worst of policy differences. In other words, personal attacks work when they're actually about candidates themselves.

The Paul-linked anti-Santorum ad won't stick because, despite its negativity, it really says nothing about Rick Santorum, a decent and committed family man, himself. Likewise, while the McCain "celebrity" attacks on Obama did highlight the current president's true celebrity status, they may have backfired: celebrities, even those with train-wreck personal lives, are, by definition, popular in much the same way that successful politicians must be.

On the other hand, the attacks on Gingrich, Kerry and Allen proved effective because they revealed deep truths: as a colleague of Gingrich at the American Enterprise Institute and co-worker of Kerry's and Allen's at the Senate, I've seen all three in action. Gingrich is conservative but the ads worked against because the thrice-married "family values" advocate is an enormous hypocrite given to cultish management theories. Kerry didn't display physical cowardice in Vietnam but he is a self-important prima donna who was personally unpopular with the Senate colleagues on both sides of the aisle, rarely had an original thought, and exaggerated his own achievements. Allen, likewise, probably didn't discriminate against people on the basis of skin color but had an enormous mean streak and, among other things, wouldn't even shake hands with people he thought were liberals.

And these questions of character may well decide elections. The differences between the Republican and Democratic parties, after all, is stark enough that about seven out of ten voters will vote something pretty close to straight party line no matter who runs (dead girl/live boy/satanic cult situations excepted.) The rest of electorate votes mostly on personal characteristics. And, for these voters, personal attacks can make a real difference when they reveal deep truths about a candidates' moral character.