If you wanted a symbolic picture of the Republican-Democratic divide, maybe it should be a split photograph of soon-to-be-House Speaker John Boehner and President Obama talking by phone.
Boehner would be on a landline and Obama would be on his cell phone.
Well, maybe that's taking things too far. But the Pew Research Center's final study
for this year of the disparities between those interviewed by landline and those interviewed by cell phone further bolster its earlier findings that landline-only samples of voters skew the results toward Republicans.
Analyzing three of its own polls during 2010, Republicans held a lead that was an average 5.1 points higher in the landline-only samples than in the surveys that combined landlines and cell phones.
Pew said that in its final pre-election poll, the landline-only sample of likely voters put the Republicans ahead on the generic congressional ballot by 51 percent to 39 percent, but that lead fell to 48 percent to 42 percent when cell phone users were included in the sample. While the official figures are not yet final, the Republican margin in the national House vote ended up being about 7 points.
Pew found this factor in play with two groups of cell phone users. It was most apparent among those who only use cell phones and don't have a landline, but it also showed up, though to a lesser degree, among "dual" users who have both a landline and a cell phone.
Pew says that in the three polls from this year that it analyzed, dual users reached on their cell tended to be younger, more likely to be black or Hispanic, less likely to be college graduates, less conservative and more Democratic in their vote preference than dual users reached by landline.
When dual users were reached by landline, Republicans had a 12-point advantage in the Pew polls on the midterm elections. But when dual users were reached by cell, the Republican margin fell to five points.
Among cell phone-only voters, the Republicans led by just three points. The overall margins of error in the Pew congressional polls for samples that included landline and cell phone users ranged from 2.5 to 3 points.
Pew cited the particular challenge of reaching younger voters because many have no landlines and because of their lifestyles. The National Center for Health Statistics
has said that in the second half of 2009, 38 percent of 18-to-24-year-olds and 49 percent of 25-to-29-year-olds lived in households without a landline.
To deal with this, Pew did twice as many interviews with voters under 30 by cell phone than it did by landline, even though, overall, the landline part of Pew's sample is twice that of cell phones.
Pew found that young people reached by cell phone differ politically from young people reached by landline.
Democrats had a 53 percent to 38 percent lead over Republicans among registered voters under 30 in Pew surveys this year that included both landline and cell phone users. But when it came to just those reached by landline, the Democratic edge fell from 49 percent to 45 percent.
One final note from Pew's findings: "Voter registration is lowest among those with only a cell phone -- just 60 percent are registered voters."
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