Eric McGhee, Chris Warshaw, and I wrote this column in today’s Washington Post on the evaporation of the U.S. House’s longstanding pro-Republican bias in the 2020s.

For more than two decades, the House was consistently biased in Republicans’ favor. Votes cast for GOP candidates translated into congressional seats more efficiently than did votes for Democrats. . . .

Now, that fixture of American politics is gone. In the 2022 and 2024 elections, according to standard measures of partisan bias, the House exhibited no pro-Republican lean at all. Of course, Republicans won narrow majorities in 2022 and 2024. But they did so because they won narrow pluralities of the total House vote. For the first time in a generation, both Republicans’ control of the chamber and their slim governing margins accurately reflected voters’ preferences. . . .

Thanks to this shift, legislative divisions over the next two years will mirror cleavages in the electorate, at least in partisan terms. And when it’s time to vote again, whichever party earns a plurality of the total votes cast in House races is likely to win the speaker’s gavel. Neither party should expect its share of House seats to be too inflated or deflated relative to its popular appeal. . . .

What spurred this change? Part of the story is a decline in extreme Republican gerrymandering. In 2012, six states’ congressional plans had pro-Republican efficiency gaps of two or more seats. This decade, only one state’s map (North Carolina’s for the 2024 election) was as tilted toward Republicans. . . .

At the same time, the 2020s feature more highly pro-Democratic plans. In 2012, no map had a pro-Democratic efficiency gap of at least two seats. This decade, Illinois’s Democratic gerrymandering boosted Democrats by 3.5 seats on average. California’s commission-drawn map netted them roughly 4.5 bonus seats, possibly because the spatial patterns of the state’s voters favor Democrats. . . .

The House’s reduced tilt also reflects the country’s changing political geography. For years, some have argued that Republicans “naturally” benefit from redistricting because Democrats squander too many votes in safe urban districts. In 2024, however, cities swung to the right as Republicans made large gains among young and minority voters. That meant Democrats won most urban districts by considerably tighter margins. Concurrently, rural and exurban areas backed Republicans to an even greater extent. Districts there are now about as blood-red — i.e., as inefficient — as their deep-blue counterparts in cities. . . .

With these scenarios on the horizon, today’s unbiased House shouldn’t be a pretext for putting off redistricting reform. The House isn’t balanced because most states have fair congressional plans; to the contrary, many states have unfair plans, but Democratic and Republican gerrymanders happen to offset one another almost perfectly. This equipoise is fortuitous, but it continues to leave many Americans poorly represented by their states’ congressional delegations. Redistricting abuses also remain rampant at the state and local levels. These legislatures’ biases can’t be balanced by maps elsewhere being tilted in the opposite direction.

The need to curb gerrymandering, then, is as urgent now as when it previously distorted the House as a whole.