Cell phone omission may skew election polls

WASHINGTON – Watching the polls to figure out who’s up and who’s down this election season? Be careful. The poll may have a pro-Republican bias.

The ranks of Americans who use only cell phones have skyrocketed. But some public polls don’t survey them, missing a group of people who are more likely to vote Democratic, including the young, the poor, Hispanics and African-Americans.

The nonpartisan Pew Research Center found that in four out of five national polls this year, polls that contact only those with land-line phones gave Republicans a 4- to 6-percentage-point edge over Democrats, compared with polls that included cell phones.

In the most recent poll, a survey of likely voters reached via land lines gave Republicans a 12-point edge, 53-41 percent. Polls that also called voters who only use cell phones found the Republican edge was 7 points, 50-43 percent.

“Cell-only adults are demographically and politically different than those who live in land-line households,” the Pew report said. “As a result, election polls that rely only on land-line samples may be biased.”

The challenge in measuring public opinion has grown as more Americans rely on cell phones. In 4  1/2 years, the percentage of Americans 18 and older who rely only on cell phones has skyrocketed from 9.6 percent to 22.9 percent, according to the National Center for Health Statistics.