Every election it's the same old story: People grouse about the negative TV ads, and they insist that the ads have no bearing on how they vote. Yet, in every election and with increasing frequency, the strategists air their video sewage. Why do you suppose that is?

Because negative ads work. Because even though the voters voice disdain, they remember the messages.

The Iowa Republican caucuses have been a veritable laboratory for these truisms. Regardless of who wins or loses tonight (or, more precisely, regardless of who manages to best spin a loss into a perceived victory), the successful anti-Gingrich fusillade is a blueprint for more poison warfare on the '12 campaign trail.

The stats speak for themselves. At the dawn of December, Newt Gingrich was Mitt Romney's chief rival, drawing support from roughly 30 percent of likely Iowa Republican caucusers. As of today, Newt's support has been cut in half, and the percentage of caucusers who deem him "unacceptable" has more than doubled. And Newt knows why: "I'm carrying the weight of $3.5 million of negative ads."

The operatives at Restore Our Future, a Romney-allied "independent" group, would not have ponied up all that money without first calculating that the ads would work, that people would ingest the negative attacks on Newt even as they condemn the negativity. The ad makers bet correctly. By the time the smoke cleared, Newt had been painted as a Beltway sleazebag who took money from special interests, violated the House ethics rules, sucked up to Nancy Pelosi, and sold out the conservative movement.

In short, Newt has "too much baggage" - an ad phrase reinforced by the video image of bags on an airport carousel. Sure enough, some grassroots Iowa Republicans are now telling reporters that Newt has "too much baggage."

Nothing new there. Negative attack ads can backfire sometimes, but, far more often, they're a fabulous way to mold voters' minds. They're particularly effective when employed against a candidate who is not well known - someone like '88 Democratic nominee Michael Dukakis (the Bush-friendly attack ads defined him as a polluter who was soft on crime), or someone like '04 Democratic nominee John Kerry (the Swift Boaters defined him as a wimp and fraud who basically faked his war heroism). Dukakis and Kerry, being Democrats, failed to fight back until it was too late - thereby cementing the ads' effectiveness.

Newt had two vulnerabilities in Iowa. He wasn't very well known - yes, he once was a House Speaker, but he quit that job 13 years ago - and that made him grist for negative ad definition. But a lot of Iowans had recently heard some bad things about him - via the debates, he had acknowledged earning big money from Freddie Mac - and negative ads are a great way to exploit latent voter suspicions about a candidate. Then it's just a matter of connecting the dots and filling in the gaps.

Granted, the Restore Our Future attack team frequently exaggerated its case - one ad declared that "Pelosi and Gingrich co-sponsored a bill," without mentioning that this apparently blasphemous bipartisan gesture occurred in 1989 and that the bill in question had 144 co-sponsors - but, for many Iowa Republicans, the anti-Newt messages apparently had the broader ring of truth. They were prepared to believe the worst about Newt, and the ads made the job easier.

That's one big reason why negativity so often works. Voters may not like the ads, but their baseline dislike of politicians conditions them to remember the ads. Academics have talked about that in their research, and political strategists have long believed that in their gut. Way back in 1990, in fact, a Democratic operative named George Shipley told me that video attacks work well in a cynical era: "The public no longer has faith (in politicians). So voters pay more attention to character. Negative ads have more memorability."

It also helps when the targeted candidate is virtually broke. There was a week in mid-December when Restore Our Future outspent Newt's campaign by a ratio of 34 to 1. For that, we can thank the John Roberts Supreme Court, which, in the name of free expression, now permits these "independent" groups to accept unlimited, anonymous donations. Restore Our Future is staffed with Romney allies; they are barred from coordinating with the Romney campaign, but they don't need to. They knew that Newt had to be taken down, and they already knew what thematic buttons to push. We'll be seeing a lot more of these groups in 2012, in both parties. The video sewage has barely begun.

But before we despair, perhaps some perspective is required. Perhaps we're just talking here about human nature. A Texas Democratic ad strategist, Dean Rindy, told me a long time ago that "Politics is war conducted by civil means, and passions will run high. They always have." By way of example, he recounted a 19th-century debate in the British Parliament between liberal icon William Gladstone and conservative icon Benjamin Disraeli. Gladstone predicted that his foe would die either on the gallows or from a bout of syphilis - to which Disraeli retorted, "That, sir, depends on whether I embrace your principles or your mistress."

"Boy," Rindy smiled, savoring the yarn, "I wish we could write copy like that."


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