Media Polls:
ABC News Polling Unit (1999–present)
American National Election Studies (ANES)
The Associated Press/IPSOS Poll (2003–present).
CBS News Polls (2008-present). Using CBS News Poll Database feature allows topical searching of CBS polls since 1976.
Fox News Polls (2007–present).
The Los Angeles Times Polls (1996–present)
National Opinion Center (NORC.) Specialized international and domestic surveys. The earliest survey dates to 1941. Components of some studies can be downloaded.
The New York Times Polls (2002–present)
NPR/KAISER/Kennedy School Polls A handful of polls from the last decade on a variety of topics.
Pew Hispanic Center The Pew Hispanic Center was established in 2001 and offers data, publications and datasets that are downloadable free of charge.
Pew Internet & American Life Project Free access to downloadable datasets dating back to 2000.
Pew Research Center for the People & the Press Data Archive Survey reports and downloadable datasets from 1997 to the present.
Pew Social & Demographic Trends Studies behaviors and attitudes of Americans in key realms of their lives, including family, community, health, finance, work and leisure.
Rasmussen Reports Details polling on current events and trends.
Real Clear Politics Latest Polls Details very latest polling information on Presidential Job Approval, Direction of Country, and Elections.
University Polls:
Marist Polls Polls from New York state and the key primary state New Hampshire.
Quinnipiac University Polling Institute Quinnipiac tracks presidential politics in key battleground states.
Other Polls:
Public Policy Polling Polls about current politics at the state and national level.
Gallup "Combining more than 75 years of experience with its global reach, Gallup knows more about the attitudes and behaviors of the world's constituents, employees, and customers than any other organization."