Where do you get your data?
Map shapefiles are from UCLA Political Science Department and Jeffrey B. Lewis, Brandon DeVine, Lincoln Pitcher, and Kenneth C. Martis (2013-2018), as well as OpenDataDC (2022) and the U.S. Census Bureau (2018) and ESRI (2021). Election data comes from the Almanacs of American Politics (with individual authors being credited in the info section of every map, as there are so many of them), as well as Professor Gary Jacobson (2018), Wikipedia (2022), Dave Leip's Atlas of U.S. Presidential Elections (2022), POLIDATA (2022), Kenneth Black (2022) and The Congressional District Data Book, Districts of the 87th Congress under the direction of Edwin D. Goldfield (1961); data tabulated int spreadsheet format by Kenneth Black and DailyKos member Xenocrypt.
Who makes these maps?
These maps are made by Kiernan Park-Egan, a graduate student at Northwest Missouri State University with a B.A. in Environmental Studies with and Emphasis in GIS from Western Washington University.
How far back do these results go?
Full results by congressional district are hard to come by. We have percentages for each district going back to 1952, but we lack vote totals for some of these elections as well. Results that go further back are those that come from districts that didn't split counties and whose data is already available publicly online. Unfortunately our access to pre-1952 precinct data is very limited, so we can't tabulate results for districts that split counties for those past races, at least for most states.
Can I help you find data for past elections?
Yes! We would be very grateful if you could provide us access to digitized precinct data from pre-1952 elections so that we can expand our library of results. Contact @KiernanEgan on Twitter if you have any useful info.
Can I share these maps on Wikipedia or other websites?
Yes! Feel free to make hyperlinks of these maps on whatever website you wish. Credits are included in the dialogue box for each interactive map, so don't hesitate to post them. We strive to make election data publicly available for everyone.