When Andy McKenna Jr. took the reins of the Illinois Republican Party almost two years ago, he was determined to turn our blue state red–or at least closer to purple. The party was in ruins, due in part to the indictment of former governor George Ryan and the decision to import Alan Keyes from Maryland to run for the Senate against Barack Obama. McKenna, who’d made his political debut in the 2004 Senate primary–spending $4.4 million, more than half of it his own money, and coming in dead last–says everyone kept giving him the same advice. “The biggest thing I heard was grass roots, you’ve gotta focus on the grass roots. My experience is in business, so I didn’t have any experience with grass roots.”

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Campaigns have always used state voter files to identify loyal partisans and those who need an extra nudge to get to the polls. With Voter Vault a Web-based interface allows party workers and volunteers to add the information they glean when knocking on doors and making phone calls, determining if you’re pro-life or support the war in Iraq. Next comes a third layer: data purchased from commercial marketing companies. The magazines you subscribe to, the kind of car you drive, the number of TVs you own, whether you use a Mac or a PC–that’s all in the system. Finally your profile gets topped off with public information like census data: the race and income mix of your neighborhood, how many people own their homes and how big the homes are, how far you and your neighbors commute to work. If you’ve got a hunting license you’re probably against gun control, and since that license is public record, it’s collected as well. Even if you’ve never been to the polls, Voter Vault can help determine how you might cast a ballot.

The Republican National Committee started developing Voter Vault in 2000, spurred by the success of the union-propelled voting drives the Democrats had mounted in Florida and other states. It was first used in targeted congressional races in 2002, when the party picked up some new seats in both houses. And in 2004, when the GOP hammered swing states with money and people, Voter Vault guided the effort. The Democratic National Committee tried playing catch-up during the 2004 election, morphing its e-mail list into something it called, variously, Datamart and Demzilla, but the system never really got off the ground, and by late 2005 it had been abandoned.

Campaign finance restrictions have forced many Democratic candidates to hire microtargeting consultants like Ken Strasma, president of the Washington, D.C., firm Strategic Telemetry. “We’re able to take several hundred different indicators from the census and commercial marketing data, look at people who do have primary history, and see what they look like demographically,” says Strasma. “Even if you’re not able to say people who drive four-door foreign cars are Republicans, period, end of paragraph, you can come up with scores that say, these people with this combination of 350 census indicators are 60 percent likely to be Democrats.”