ContentsDorling cartogram
United States · presidential returns, 2000–2024
Dorling cartogram
Presidential vote by county draws county returns as circles sized by votes cast, because a choropleth of election returns gives each county’s share its land area. At county scale the circles collide, and what a collision hides is always a place with people in it. Los Angeles covers Orange and Ventura; the corridor from Boston to Washington is one shape.
A Dorling cartogram separates them. Each circle keeps its area, which is the quantity, and moves out of its neighbours’ way. The result is readable, and a circle’s position is only roughly its county’s. The ticks mark the true positions, and the caption under the panel says how many circles moved and how far.
The arrangement is solved once, against 2020, and reused for all 7 cycles. Re-solving each time would move every circle whenever the data changed, and a reader could not tell whether a pattern came from the vote or from the layout.
Change the cycle
Cycle
The cycle changes the colours on both panels and the circle sizes on the left. On the right, the sizes and the arrangement are 2020’s in every cycle, and both panels use colour classes cut on 2020’s shares, so a circle that keeps its colour from one cycle to the next stayed in the same class.
Democratic two-party share, 2024
3,108 counties in the lower 48 states and DC. Colour is the two-party share in 2024. Circle area is votes cast: in 2024 on the left, and in 2020 on the right, where the circles are moved apart.
5 classes of equal width, 15.6 points each, placed symmetrically about 50.0%, cut on 2020’s county shares and used for every cycle. Red is Republican and blue Democratic.
- Shows
- Quantity, without a large county's area standing in for it and without a dense county's neighbours hiding under it. Every circle on the right is its 2020 size in all 7 cycles, and the colour classes are fixed too, so a colour change between cycles is a change in the vote.
- Hides
- Position. A moved circle is not at its county: the ticks mark where each one came from. Shape and adjacency are gone too, so this cannot be read as a map of who borders whom. Holding 2020's sizes fixed means a county whose turnout fell is still drawn at the size it used to be; that is what makes the colours comparable, and it is a claim about the sizes rather than a fact about them.