Dave Leip's Atlas of U.S. Elections (Available in DiSC Lab)
Available at the DiSC lab. E-mail email@example.com for access.
Presidential general election data at the state, county, and New England town level (1992–2016)
Presidential primary elections data at the state, county, and New England town level (2000–2016)
Voter registration and turnout data for all 50 states, counties, and New England towns (1992–2016)
Data in Excel. In addition the web version contains maps and tables of all this data plus Presidential general results back to 1789. Note: Democrats are represented in red and Republicans in blue contrary to the more recent practice.
Primary election returns from all Democratic and Republican primaries for the US House of Representatives for 1956-2010 at the Congressional District level. (Compiled from the America Votes series.) Also includes district-specific variables, as well as data about candidate backgrounds and gender for recent years.
ICPSR data collection of county-level electoral returns for all parties and candidates. Data are most complete from 1824 on. 1950–1990 are available as election year files; 1824–1950 are multi-year state files. (Also includes congressional and gubernatorial elections.)
County-level returns for elections to the United States presidency and to the United States House of Representatives for the years 1840 to 1972. The variables for the presidential vote include the percentages of ballots cast for major and "significant" minor party candidates, and estimates of voter turnout in the presidential elections. There are similar variables for the congressional vote except that returns are reported for parties and not for candidates. Congressional district numbers are also reported for each county for every election.
Searchable collection of early American election returns, including U.S. Senate and House of Representatives elections. Narrow by state, year, office, jurisdiction, party, and election type. Full datasets for each state can also be downloaded.