The biggest story of Tuesday’s election is that Democrats overcame Republican gerrymanders intended to lock them out of power in the House of Representatives. In the long run, however, an even bigger story may be that gerrymandering itself suffered a significant loss last night.

Michigan, one of the most gerrymandered states in the Union, overwhelmingly approved a state constitutional amendment which provides that future legislative maps will be drawn by an independent commission. At the peak of its effectiveness, in 2012, Michigan’s gerrymander allowed Republicans to win 9 of the state’s 14 U.S. House seats, despite the fact that President Obama won the state by over 9 points that year.

This victory for democracy is part of a larger pattern. Ohio approved a ballot measure last May which creates a Rube Goldberg-like series of obstacles to lawmakers seeking to gerrymander that state. Pennsylvania’s Supreme Court struck down that state’s gerrymandered maps last January — allowing Democrats to gain three seats in that state yesterday. And one more large state will likely see its gerrymanders fall shortly.

North Carolina’s legislative maps are so aggressively gerrymandered that, even though the state frequently has competitive statewide elections, Republicans currently hold veto-proof majorities in both houses of the state’s legislature. They lost those supermajorities in the incoming state house, but will still dominate both houses. After yesterday’s election, however, Democrats will control a 5-2 majority on the North Carolina Supreme Court. That means that they can bring Pennsylvania-style gerrymandering reform to that state.


Of course, this is only four states in a nation with 50 — but Michigan, Ohio, Pennsylvania, and North Carolina are all large states, and that means that their gerrymanders had significant implications for the U.S. House.

Because small states only have one or a handful of House seats, lawmakers can only do so much in those states to rig their congressional maps. Big states provide more gerrymandering opportunitues — leading to situations like Ohio, a swing state where Republicans drew maps that allowed them to win 75 percent of the congressional seats in a year when Obama won the state as a whole.

There is, however, one caveat to any optimism that gerrymandering could be on the wane. Two years ago, in Arizona State Legislature v. Arizona Independent Redistricting Commission, the Supreme Court rejected a suit claiming that only state legislatures — and not independent redistricting commissions created by a ballot initiative — may draw legislative lines. Pennsylvania Republicans have argued, thus far unsuccessfully, that a similar argument should prevent state supreme courts from halting gerrymandering.

But Arizona State Legislature was a 5-4 decision, with retired Justice Anthony Kennedy casting the key fifth vote. There is a very real risk that Republican Brett Kavanaugh will disagree with Kennedy and provide the fifth vote to declare all of this progress against gerrymandering unconstitutional.