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This polarization seems to confirm the anecdotal experiences of many people, who report they are increasingly living among like-minded neighbors. Indeed, in the months since the November election, political viewpoints appear only to have solidified, further erasing the prospect of a "purple" middle ground between a "blue" left and a "red" right.
When FiveThirtyEight.com’s David Wasserman compared county voting patterns from 2016 to past elections, he concluded that purple America has all but disappeared.
“More than 61 percent of voters cast ballots in counties that gave either Clinton or Trump at least 60 percent of the major-party vote last November,” he wrote for the data-centric political and sports hub. “That’s up from 50 percent of voters who lived in such counties in 2012 and 39 percent in 1992—an accelerating trend that confirms that America’s political fabric, geographically, is tearing apart.”
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Other data crunchers don’t quite think purple America has vanished, but rather that it migrated to the outskirts of urban areas. That trend is blurred by looking at election results based on county-line borders. Statisticians discussing FiveThirtyEight’s report in online forums said mapping political views by population grids is a better metric than by county vote totals.
Breaking down voting patterns by population density confirms that political views are becoming more geographically concentrated. But it also shows a lot of blue, purple and red out there in 2016—far more than just looking at a county-level analysis.
“If the map were drawn instead as a grid of squares of equal population you’d see slightly more blue than red with both hues getting deeper over time,” wrote AKADriver on reddit.com’s DataIsBeautiful page and thread discussing Wasserman’s report.