http://www.icpsr.umich.edu/cocoon/ICPSR/SERIES/00059.xml

[Available to ICPSR members only - most U.S. higher education institutions are member institutions!]

“The United States Historical Election Returns series was developed by ICPSR and was supported by grants from the National Science Foundation and the National Endowment for the Humanities. ICPSR’s holdings of historical election data cover the years 1788-1990 and consist of several discrete datasets that contain county- and state-level returns for all elections to the offices of president, governor, United States senator, and United States representative.”

I haven’t used the files yet. I will post the resulted maps later..