ABC conducted polls with archives going back to 1999.

Associated Press/IPSOS polls. IPSOS is a global advertising research company.

Current year opinion polls conducted by CBS.

On the front page of the National Journal, under "Columns and Features" click on "Poll Track".

New York Times polls going back to 2002.

The Pew Research Center is a nonpartisan "fact tank" that provides information on the issues, attitudes and trends shaping America and the world. It does not take positions on policy issues.

The Pew Global Attitudes Project is a series of worldwide public opinion surveys that encompasses a broad array of subjects ranging from people's assessments of their own lives to their views about the current state of the world and important issues of the day. More than 150,000 interviews in 54 countries have been conducted as part of the project's work.

Some free materials on national polls. Other material is for pay.

Presents polls and analysis with visualizing of polling results graphically

RCP culls and publishes the best commentary, news, polling data, and links to important resources from all points of the political compass and covering all the important issues of the day. RealClearPolitics has become a trusted filter for anyone interested in politics.

SurveyUSA is an independent, non-partisan, full-service opinion research firm that conducts scientific research for media, government, and private-sector clients. By many measures, SurveyUSA is the nation’s largest public opinion polling firm. As of 2002, 19 of the nation’s then 25 largest media companies had contracted with SurveyUSA to conduct opinion research.