In 2012, 160 counties cast about the same number of votes as the rest of the country. But, your run-of-the-mill election map won’t show you that.
Because electoral votes are based on voting population not land area, maps of election polls and results often provide a misleading view of the data. When mapped to a standard cartographic projection, the map will over emphasize the states with fewer electoral votes per square mile and underemphasize the high density areas. This is especially notable in the Northeast where high population with large amounts of electoral votes are diminished visually by the state’s small geographic size.
When looking at an election map to see proportionality, perhaps a cartogram would be better suited.
The Washington Post recently published a very interesting article on the topic that included these graphics and more. Want to learn more about the visual balance and perception of election maps? Read on (source): Election maps are telling you big lies about small things – Washington Post