MUST SEE TV: The Entire History Of 20th Century Presidential Election Patterns In One Minute Or Less

DAVID B. SPARKS: A few weeks ago, I shared a series of choropleth maps of U.S. presidential election returns, illustrating the relative support for Democratic, Republican, and third Party candidates since 1920. The granularity of these county level results led me to wonder whether it would be possible to develop an isarithmic map of presidential voting using the same data. Isarithmic maps are essentially topographic or contour maps, wherein a third variable is represented in two dimensions by color, or by contour lines, indicating gradations. I had never seen such a map depicting political data — certainly not election returns, and thus sought to create them. Comparison of these maps across time also underscores well-known political trends […] Note the nearly inverted maps for 1924 and 2004, between which elections the Solid South went from solidly Democratic to solidly Republican. Interestingly, though that particular regional pattern has been remarkably consistent since 1984, the South favored a Democratic candidate as recently as 1980. These patterns over time are even better observed in motion. Interpolating support between elections, I have generated a video in which these maps shift smoothly from one election year to the next. The result is the story of 20th century presidential politics on a grand scale, condensed into a little 0ver a minute of data visualization. MORE