Here's what the electoral map would look like if votes were determined solely by population density, measured by the average number of people that live within a 5 mile radius of you.

Data from here. https://fivethirtyeight.com/features/how-urban-or-rural-is-your-state-and-what-does-that-mean-for-the-2020-election/

In certain ways, this should be slightly comforting to Democrats. Urbanization isn't intrinsically a disadvantage to them in the Electoral College. But they have been underperforming in states that are fairly urban, namely Texas, Florida, Arizona, and more recently, Pennsylvania.