The idea is an outgrowth of techniques that businesses have long used to find new customers. Using publicly available data, the Bush campaign in 2004 knew voters' favorite vacation spots, religious leanings, the music and magazines they liked, the cars they drove.

Few people might realize how much information is publicly available, for a price, about their lifestyles. Companies collect and sell consumer information they buy from credit card companies, airlines and retailers of every stripe.

And it's not just the Republicans:

The California Democratic Party -- which heads the statewide turnout operation for Schwarzenegger's rival, state Treasurer Phil Angelides, and other party candidates -- has been gathering consumer information as well.

But Schwarzenegger and national Republicans appear to be making more elaborate use of such data.