10/26/2006 - Political pollsters continue to cast a wary eye on the growing number of Americans who only have a cell phone and no landline. The Pew Research Center estimates that this group now constitutes one-in-ten adults, and its demographic characteristics are very different from the landline population. But three Pew surveys of cell-only Americans this year, including a political poll earlier this month, have found that the absence of the "cell-only" population from telephone surveys is not creating a measurable bias in the overall findings.
Pew's early October survey of 2,004 adults, conducted Sept. 21-Oct. 4 in conjunction with the Associated Press, included a sample of 200 people who were reached on their cell phone and said that they had no landline phone. As previous studies of the cell-only population have shown, this group is younger, less affluent, and includes a greater proportion of men and minorities than does the landline sample.
However, the political attitudes of cell-only respondents are not substantially different from the landline respondents. In the generic congressional ballot, the Democrats held a 20-point lead among the cell-only sample (54%-34%), and a more modest 13-point lead in the landline sample. But when the cell-only respondents are included with the respondents reached on a landline and this blended sample is weighted to match the full U.S. population demographically and with respect to telephone status the overall estimates of the vote are unaffected.
Read the full report Cell-Only Voters Not Very Different; Fewer Registered, More First-time Voters on the Pew Research Center Web site.