US election 2020: what do the county-level returns indicate?

High-return counties favour Donald Trump, but Joe Biden is turning more counties blue.

EDGEWATER, CO - NOVEMBER 03: A mail in ballot collection box is seen at Edgewater City Hall on November 3, 2020 in Edgewater, Colorado. After a record-breaking early voting turnout, Americans head to the polls on the last day to cast their vote for incumbent U.S. President Donald Trump or Democratic nominee Joe Biden in the 2020 presidential election. (Photo by Marc Piscotty/Getty Images)

Among the 3,141 counties in the US, 1,779 had counted 90 per cent or more of their expected votes by early Tuesday morning, according to the New York Times estimated vote counts.

Donald Trump leads in about 90 per cent of those counties, but Joe Biden has potentially turned 28 counties from their 2016 Trump majority. Trump has potentially turned 11 counties red this election.

Trump has flipped 11 counties so far

Counties that have flipped from a Democrat winning margin in 2016 to a Republican one in 2020

These Biden-led counties have, on average, gained nine points from their 2016 margins in order to cross the line to Democratic majority. Trump-led counties have, on average, gained 13 points from 2016 to cross over to Republican majority. These figures are substantially skewed by one place, however, which saw a remarkable result: Charles County in Maryland, which pivoted from a 30 point Democratic lead in 2016 to a 37 point Republican lead in this election.

If we exclude Charles County, the average Trump gain in the counties he flipped drops from 13 points to just seven points.

Biden has flipped 28 counties so far

Counties that have flipped from a Republican winning margin in 2016 to a Democrat one in 2020

Alexandra Kanick is a data reporter at City Monitor, a New Statesman Media Group publication