A data-driven blog that uses chart, maps, cartograms, and other visualizations to understand important societal issues.


Election Morphing: Animated Cartogram of the 2020 Election

The headline: How the 202 election looks different mapping results by county area and by county population.

The movie: The movie illustrates county-level results for the 2020 election. The starting frames map the US counties in traditional format, where the visible area of each county is proportional to its actual area. Consequent frames morph each county so that the area of each county is increasingly proportional to its population not just area (i.e., a cartogram; https://tinyurl.com/yxlkh93z). In the final frame, each county is proportional only to its population, before morphing back to a traditional map. The summed area of all the counties in every frame is identical, and the county with the smallest area in each frame—whether its smallest based on population or actual area or somewhere in between—is also identical. Each county is colored proportionally to the 2020 election: Red counties voted for Trump, ranging from dark red (strongly Trump; >75%) to light red (marginally Trump; 50–55%). Blue counties voted for Biden, ranging from dark blue (strongly Biden; >75%) to light blue (marginally blue; 50–55%).

The analysis: There are 3,142 counties in the US. Alaska does not report votes by county (29 counties) and Kalawao County in Hawaii did not have election data reported here. (In 2016, Charted Territory assigned Alaska votes to counties using dasymetric mapping.) This leaves 3,112 counties. Of these, 2,579 counties voted for Trump and 533 for Biden. 131 million people now live in counties that voted for Trump and 197 million live in counties that voted for Biden. Because many low-population counties voted overwhelmingly for Trump, the standard county map has a strong deep red feel. This disappears with the cartogram where county areas are entirely proportional to population.

The data: Election data were sourced from Politico (https://www.politico.com/2020-election/results/president/). Cartograms were built using Scape Toad (http://scapetoad.choros.place/).  Figures and animations were developed by Charted Territory.

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