Based on @mbostock’s Coastal Graph Distance map. So the major caveat is that it measures distance by how many counties away you are from a coastal county, not by actual physical as-the-crow-flies distance; notice how the pulsing isoline races across the county-sparse West and crawls along the county-dense East.
Using @mkearney’s election result data. Inspired by Lorcan’s tweet positing a positive correlation between distance from the sea and support for Donald Trump, which appeared weak in the final election. An update of my earlier block based on the Republican primary.