iPOLL (Roper Center Services at Vanderbilt)Includes full-text, question-level summary data from public opinion polls from major survey research organizations in the United States, including the Gallup Poll, Roper Center for Public Opinion Research, Harris, the National Opinion Research Center at the University of Chicago, ABC News, CBS News, NBC News, the Los Angeles Times, The New York Times, USA Today, The Washington Post, and the Associated Press.