Competitive seats fall victim to redistricting pens

State legislators tasked with redrawing political boundary lines in the decennial redistricting process over the last year took aim at what was already an endangered species in modern politics: competitive districts.

An analysis of old and new district lines, conducted using data produced exclusively for Pluribus News, shows the number of state legislative districts where President Biden and former President Trump received roughly equal shares of the vote dropped precipitously after lawmakers drew new maps.

At the same time, the number of districts where Biden or Trump received more than 55% of the vote grew — a sign, experts said, that legislators used the remapping process to alter competitive districts into seats that are more likely to sit safely in the Republican or Democratic columns for the next decade.

“The really competitive districts are declining,” said Brian Amos, a political scientist at Wichita State University who compiled the data. “That’s basic redistricting strategy, if you’re not being neutral about it. Republicans are going to draw a lot of seats where they’re 55-60% favored, and Democrats are going to draw a lot of seats where they’re 55-60% favored. They don’t like the uncertainty of a 50-50 district.”

In the 2020 election, Trump took 50-55% of the vote in 580 state legislative districts across the country. Biden claimed 50-55% in 578 districts. Under the new lines drawn by legislators after the 2020 census, which took effect for this year’s midterm elections, Trump would have carried 546 districts and Biden 536 districts in that percentage range.

The number of districts both candidates won with more than 55% of the vote grew from 5,124 under the old lines to 5,185 under the new versions.

Magnifying trend

The makeup of the new districts magnifies the increasing political polarization across the nation. Legislators, who control the redistricting process in most states, used that authority to carve out safer seats for their colleagues, locking in advantages for the next decade to come.

“There’s no incentive for politicians to make competitive districts,” said Michael McDonald, a redistricting expert at the University of Florida who reviewed the data. “It’s in no incumbent’s interest, it’s in no political party’s interest. You want the safe district over the chances of getting one or two competitive districts. The strategy really is to do away with competition.”

The same phenomenon played out in federal redistricting, where state legislators shored up virtually every potentially competitive seat possible over the last two years. An analysis by the Brennan Center for Justice found that new congressional district lines include just 30 seats that Biden won by less than 8 percentage points, and 30 seats that Trump won by the same narrow margin.

There is some evidence that handing legislators the power to draw lines leads to fewer competitive districts. Michael Li and Chris Leaverton, the authors of the Brennan Center study, found that the number of competitive seats in states where Republicans or Democrats controlled the remapping process led to a steep decline in competition. In states where independent commissions or courts drew the maps, the number of competitive seats tended to increase.

“All told, there are now fewer competitive districts than at any point in the last 52 years,” Li and Leaverton wrote. “If the good news is that both parties emerged with reasonable opportunities in coming years to win control of a closely divided House, the bad news is that they will fight that battle on the narrowest of terrains under maps artificially engineered to reduce competition.”

Optimizing vote share

McDonald, the University of Florida political scientist, pointed to another phenomenon within the state legislative district lines: The number of districts that voted most overwhelmingly for Biden or Trump also declined with the new maps.

Trump won 575 state legislative districts in 2020 with more than 75% of the vote. If the same election had been run under the new lines, he would have won 568 districts with such an overwhelming share. The total number of districts that gave Biden the same margin would have dropped from 701 under the old lines to 674 under the new.

That is a sign, McDonald said, that legislators used their authority to optimize their vote share, spreading key voters across district lines rather than concentrating too many core constituencies together.

“There’s some efficient level of partisan strength in districts. Having them overpacked wastes your votes,” McDonald said. “You want to cram your opposition into as many safe districts as you possibly can. That’s certainly part of the packing strategy.”