Our project to calculate the 2020 presidential results for all 435 congressional districts nationwide goes to O-H-I-O. You can find our complete data set here, which we're updating continuously as the precinct-level election returns we need for our calculations become available.
Despite Democratic hopes, Donald Trump’s 53-45 win in Ohio matched his 52-44 performance in this one-time swing state four years ago. Trump also carried the same 12 congressional districts that he took last time, while the remaining four Clinton seats also went for Biden. Likewise, all the Trump districts remained in GOP hands, while the four Clinton/Biden districts once again elected Democratic members. You can find a larger version of our map here.
Democrats were optimistic that Biden could flip the 1st District in the Cincinnati area, and the seat did move to the left. However, while Trump’s 51-48 showing this time was notably weaker than his prior 51-45 performance, veteran Republican Rep. Steve Chabot still rode to a 52-45 victory over Democrat Kate Schroder.
Trump secured single-digit victories in three other seats. The 10th District in the Dayton area supported him 51-47, which was a slip from his 51-44 win last time. Longtime Republican Rep. Mike Turner, though, again ran well ahead of the ticket and beat Democrat Desiree Tims 58-42.
The 12th District in the Columbus suburbs, meanwhile, went for Trump 52-46, which was quite a bit narrower than his 53-42 performance in 2016; Republican Rep. Troy Balderson, though, won 55-42 against Democrat Alaina Shearer. Trump also prevailed 54-45 in the 14th District in the Cleveland suburbs, which was down a little from his prior 54-42 win, though Republican Rep. David Joyce racked up a strong 60-40 win over Democrat Hillary O'Connor Mueri.
Biden, by contrast, lost ground in the 13th District, ancestrally blue turf in the Youngstown area with a large white working class voting bloc. This constituency had already moved dramatically to the right: Barack Obama carried it 63-35 in 2012 but Clinton won it just 51-45, and Biden hung on by an even narrower 51-48 margin. Democratic Rep. Tim Ryan beat former Republican state Rep. Christina Hagan by a stronger 52-45 spread, but it was by far the narrowest victory in his 10 House campaigns.
These results owe much to the extreme gerrymander that Republicans passed in the last round of redistricting, which has locked in a 12-4 congressional majority for the GOP every single year, even when Obama won Ohio in 2012. There's a good chance the coming decade will see something similar.
Voters passed a constitutional amendment in 2018 that theoretically puts congressional redistricting in the hands of a commission that includes members from both parties. However, if the commission's proposals don’t achieve the bipartisan support the amendment requires, the Republican-led legislature would be able to just pass its own maps again. Those maps would only be good for four years instead of the usual 10, but the process would just repeat itself. In other words, anyone who wants to gerrymander just needs to pass new maps more often.