This short story from the New York Times is one of my absolute favorites, the data are simple: it’s just US population data, and voter turnout.
The goal here is simple: give an understanding of who votes in primaries in the US electoral system. Narrowly, the audience are readers of the New York Times, but the more implicit target is really those interested in the then-ongoing primaries.
I think the simplicity of the setup makes this incredibly effective: it builds a complex picture of the American electorate in 6 simple steps. By building it layer by layer, it breaks down a complex topic into very simple terms.