The chart, created by Conor Sen using the Cook Partisan Voting Index and census data, confirms what other analysts have already observed. That is: not only do the two ends of the density spectrum gravitate toward opposing political parties, but there seems to be a consistent tipping point. Around 800 to 1,000 people per square mile, party preference switches.
Whether the apparent trend represents a solid link between population density and party affiliation remains to be seen, Emily Badger writes. Until then, the possibility that our proximity to others might directly influence our political leaning is intriguing.