Federal Election Commission -- link to the compilation of the official, certified federal election results obtained every two years from each state’s election office and other official sources. The site provides the primary, runoff, and general election results for the U.S. Senate, the U.S. House of Representatives and, when applicable, U.S. President from 1982 to the present.
National Archives: Historical Election Results -- this site contains the electoral votes and popular votes from 1789 to the present. Also include are interactive Electoral College Maps that allow you to view and analyze past results from 1964 to the present.
A New Nation Votes: American Election Returns 1787-1825 -- a searchable collection of election returns from the earliest years of American democracy compiled by Philip Lampi of the American Antiquarian Society. Election data encompasses all offices from the Federal to the local levels including Presidential elections and is obtained from newspapers and original election ballots as well as sources such as County histories that were published in the 19th century.
Descriptions of resources are adapted or quoted from vendor websites.