UNIDENTIFIED FEMALE: A CNN viewer wants to know, concerning presidential polls, how many actual people are physically polled, and are they the same people each time? How are the people selected, and what is the cross-section?</s>KEATING HOLLAND, CNN POLLING DIRECTOR: Well, Rudy, we usually interview about a thousand people for every poll, but that can drop down to 600 or 700 if we don't have enough time to do a thousand interviews. The important question is how those people are chosen, and the answer is a process called random digit dialing. A computer will randomly generate the last seven digits of telephone numbers across the country. We'll call them. We don't know anything about those people except their telephone number. But that does mean that every household with a telephone in this country has an equal chance of being selected. And no, we don't as the same people questions over and over again. We try to make sure -- in fact, random digit dialing virtually guarantees -- that we're only going to ask one household one time.
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