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Results are based on telephone interviews with 1,001 adults, 18 and older, conducted June 18-19, 2007. Results are weighted so that the sample demographics match Census Current Population Survey parameters for gender, age, education, race, region, and population density. The overall margin of sampling error is plus or minus 4 percentage points. In addition to sampling error, the practical difficulties of conducting surveys can also introduce error or bias to poll results.
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