The AP-GfK Poll was conducted Dec. 5-9 using KnowledgePanel, GfK's probability-based online panel. It involved online interviews with 1,367 adults. The survey has a margin of sampling error of plus or minus 3.5 percentage points for all respondents.
Using probability sampling methods, KnowledgePanel is designed to be representative of the U.S. population. Respondents to the survey were first selected randomly using phone or mail survey methods and were later interviewed for this survey online. People selected for KnowledgePanel who didn't otherwise have access to the Internet were provided with the ability to access the Internet at no cost to them.
Associated Press News Survey Specialist Dennis Junius contributed to this report.