270toWin.com has an interactive map of presidential elections.
Atlas of American Presidential Elections contains extensive data and maps of presidential elections.
Congressional History by the Office of the Clerk of the U.S. House of Representatives gives roll call votes from 1990.
Federal Elections Commission (FEC) is an indepedent agency that discloses campaign finance information.
Historical Statistics of the United States contains historical voting data.
Inter-Parliamentary Union contains data about the composition of parliaments throughout the world.
Inter-University Consortium on Political and Social Research (ICPSR) offers a huge amount of data on surveys.
- Election 2000@ICPSR offers downloadable data from the 2000 election.
Latin American Public Opinion Project (LAPOP) 2004-present; in 2004, LAPOP established the AmericasBarometer as multi-country, regularly conducted surveys of democratic values and behaviors in the Americas, organized by a consortium of academic and think-tank partners in the hemisphere. The first round included voting-age respondents from 11 countries. The second round of surveys took place in 2006 and represented 22 countries from the hemisphere. The third round, 2008, included 24 countries in the Americas. The most recent round of surveys was conducted in 2010, with 26 countries from North America, Latin America, and the Caribbean, adding Trinidad & Tobago as well as Suriname to the 24 countries covered in 2006. The AmericasBarometer is the most expansive regional survey project in the Western Hemisphere.
Latin American Women in Numbers (Mujeres Latinoamericanas en Cifras) has voting, education and economic data about women in Latin American. Site is in Spanish.
Lijphart Elections Archive collects political data from around the world.
Living Room Candiate has videos and transcripts of presidential campaigns from 1952.
National Center for State Courts contains extensive data on the U.S. court system.
National Election Studies produces data on voting, public opinion, and political participation.
Odum Institute has extensive data sources for the social sciences, mainly public opinion polls, psychological data and North Carolina Data.
Polling the Nation has more than 14,000 surveys since 1986 conducted by more than 700 polling organizations in the United States and more than 80 other countries.
Quinnipiac University's Polling Institute offers polling data for the nation and a few selected states.
Roper Center for Public Opinion Research 1930's-present; the Roper Center for Public Opinion Research is one of the world's leading archives of social science data, specializing in data from surveys of public opinion. Most of the data are from the United States, but over 50 nations are represented. Also includes access to iPoll.
U.S. Senate holds the roll call on the votes of U.S. Senators.
World Values Survey has data from four major surveys (1981, 1990, 1995 and 1999-2001) from many countries in the world. The survey asks dozen of questions concerning politics, gender issues, religion, economic inequality, etc. Survey data available through a World Values Survey search at ICPSR.