Most metro areas swung Democratic, but the most extreme swings were toward Mr. Trump, and the biggest of those were in heavily Hispanic metros, like Miami and areas along the Texas border.

Initially it appeared that President Trump’s strength in 2020 relative to 2016 in heavily Hispanic counties might have been specific to South Florida and Texas border areas, despite the very different national origins and identities in those two regions. But data from later-reporting counties points to a national trend.

The correlation between a county’s percent Hispanic population and its swing toward Trump was 0.41. Even excluding Miami-Dade County and all of Texas, the correlation is still 0.30. The Bronx, Los Angeles, Osceola County near Orlando, and Hudson and Passaic Counties in Northern New Jersey are all at least 40 percent Hispanic and swung toward Mr. Trump by at least five percentage points.