With nearly all of the results for the presidential election now counted, it's possible to see exactly where Trump's votes came from. To do this, we've created a 3D map of every county in the US, showing how big the swing was from Democrat to Republican (or vice versa) between 2012 and 2016. Crucially, the map shows not just where the largest-percentage swings occurred, but how many voters took part in those swings — giving a clearer picture of exactly where the election was won.
It shows just how key states in the Midwest were: Other than Florida, it's the Midwest and the Northeast that show the most significant swings toward Trump. And it shows the importance of urban areas: While a swathe of deep red in the rural Midwest shows Trump's biggest swings in terms of percentage, it was the cities and urban areas in the region that contributed more voters to Trump's column. Greater Cleveland, Flint, and Detroit had more modest swings in percentage terms, but their large populations meant those swings delivered more votes.
(Note: Michigan's results are currently provisional, pending a possible recount, but it seems unlikely that any recount will dramatically change the results)
Outside the Midwest, other densely populated areas that swung toward Trump included Las Vegas Valley, the Jersey Shore, and much of Long Island. None of those swings were able to deliver those states for the Republicans, however. Traditional Republican strongholds in the South also turned out strongly for Trump, but as so many were already safe red states, the swings are much more modest. Florida, however, moved significantly Republican, with most counties outside of Miami and Orlando swinging red.
Hillary Clinton meanwhile fared best in cities and urban areas outside the Midwest, especially the East Coast, California, and the border with Mexico, but also in Houston, Atlanta, and Miami. These numbers were all very large, contributing to Clinton's majority in the popular vote — but only a few of them were in the crucial Midwest swing states that delivered Trump his victory.
The map shows a few anomalies: Massachusetts swung Democrat more than most, probably because the candidate in 2012 was Mitt Romney, the former governor. In Utah, the swing was technically a strong one to the Democrats, as Evan McMullin's campaign ate into Republican votes there, but overall the Democrats made only modest gains. Finally, Alaska does not split its votes by county, so we can only show the swing for that state overall.
The map paints a more complex picture than the notion that the Democrats can take all cities for granted, or that Republican victory relies solely on the rural vote. This varies across regions and locations, and even small changes in swing mean that urban areas, thanks to their much larger populations, can have a distinct effect on the election's outcome.