Democrats’ total vote share roughly matches their House majority.

Elections have a way of blowing up partisan conceits—see what happened to the Democratic Party’s Electoral College “lock” in 2016. This year Democrats busted one of their own cherished myths by proving that Republican gerrymanders weren’t preventing them from retaking the House of Representatives. There’s a lesson here for voters and judges. State legislatures have been drawing congressional boundaries to favor one party or another since America’s founding. During the 40 years of sustained Democratic control of the House in the late 20th century, this worked in the Democrats’ favor. As political scientist Matt Grossmann has shown, Democrats sometimes enjoyed congressional majorities nearly 10 percentage points larger than their share of the House popular vote.

Then came the Republican romp of 2010, followed by the Census and the regular 10-year redistricting to reflect population ebb and flow across the U.S. The new GOP majorities in several states drew districts that increased their representation in the House, as Democrats also did where they had a partisan advantage. For many commentators the post-2010 redistricting created a crisis of democracy by supposedly locking Democrats out of power. Days before the 2018 election the New York Times’ David Leonhardt cited Republican gerrymandering as evidence that the U.S. could “slide toward Hungarian autocracy.” Well, so much for that. Democrats last week made their largest gain in House seats since 1974 and appear to be closing in on a 233-seat House majority with several races still not called. This means Democrats will hold about 53.6% of seats—a 7.1% edge. And, what do you know, Democratic House candidates nationwide have 52.8% of votes—7.3% more than Republicans, according to the latest Cook Political Report tally.

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