Half of the US population lives in a handful of super-dense counties
From the World Economic Forum:
Somewhat related is the long-running discussion about how population density affects voting:
At about 800 people per square mile, people switch from voting primarily Republican to voting primarily Democratic. Put another way, below 800 people per square mile, there is a 66% chance that you voted Republican. Above 800 people per square mile, there is a 66% chance that you voted Democrat. A 66% preference is a clear, dominant majority.
