Congressional Elections May Get More Interesting

By David de la Fuente

Without prior announcement, Cook Political Report released its quadrennial Partisan Voter Index Report on April 7th, which is the politics equivalent of a Beyoncé dropping a new album out of nowhere or Disney surprising people with a new Star Wars trailer. It’s kind of a big deal. Invented by Cook in the 90s, the Partisan Voter Index (PVI) is an invaluable tool for grading future House races. Will they be competitive nail-biters or pre-ordained yawners based purely on the partisan breakdown of each district?

Politicians may like the yawners, but people like us love competitive races and there’s some hopeful news buried in data. A new trend toward nonpartisan redistricting has had an impact.

First things first, this is what the PVI of competitive races is and how it is determined. The good people of Cook use the results of the last two presidential elections to measure the partisan nature of each Congressional district. As in the past, the 2017 ratings were determined based on the way each district voted in the previous two presidential races. Since in 2012 Democrat Barack Obama won the national popular vote by 4% and in 2016 Democrat Hillary Clinton won it by 2%, the current rating for the country as a whole is “Democratic lean of 3%.” But that’s not the most interesting part of this report. What’s interesting is that we now have objective proof that nonpartisan redistricting matters.

Source: 2017 Partisan Voter Index Scores by Congressional District (Cook Political Report)

Of the 36 congressional districts that flipped allegiance in the presidential race between 2012 and 2016, 21 of these flipper districts were drawn in 2011 in a neutral manner, not a political or partisan one. These 21 flipper districts represented one-seventh of the almost 150 districts in states that by design or court order had lines drawn in a neutral manner. In the over 280 congressional districts where an overtly partisan process drew the lines in 2011, just 15 were switcher districts–or one in 19. That’s a major difference. To put that in perspective, only 33% of districts nationwide were drawn neutrally, but a full 58% of those districts that switched Presidential party preference between 2012 and 2016 come from these plans. (Just a note, seven districts are not drawn at all as they represent the state at-large.)

Only 33% of districts nationwide were drawn neutrally, but a full 58% of those districts that switched Presidential party preference between 2012 and 2016 come from these plans.

To be sure, flipper districts in the presidential race are only a subset of swing districts in congressional races. But from the Cook data, one finds that nonpartisan maps are more likely to create swing districts than partisan drawn districts. Here is the evidence.

Any district with a PVI between D+5 and R+5 (that is to say a district that is no more than 5% off from the national average) is considered a “swing seat.” The Cook report documents their decline over the years — two decades ago, 164 districts were swing seats, while today there are only 72. One of the reasons for this decrease is natural geographic sorting. For whatever reason, people moved near others with whom they agree politically and geographic communities begin to share homogeneous political beliefs. The other is partisan redistricting, which warped the ability to allow for swing seats in areas that they would otherwise naturally exist.

But in places that instituted nonpartisan redistricting reforms, the complexion of races changed. In California, only eight of the 53 districts were considered swing seats by Cook’s definition. After California used nonpartisan redistricting for the first time in 2011 the number of competitive races jumped to 10. That may not seem like a lot, but in the rest of the country partisan redistricting reduced competitive seats by about 30 during that same time period. Similarly, Arizona increased from two to three swing seats after its first decade of nonpartisan redistricting — despite the nationwide drop.

After California used nonpartisan redistricting for the first time in 2011 the number of competitive races jumped to 10.

Compare that to states with extremely aggressive partisan gerrymanders, like North Carolina and Ohio. In 2009, North Carolina had four swing seats, but today it has none. Ohio had eight swing seats in 2009, today it’s three. (Just as a note, for this section about the change between decades, we had to extend swing seats to those that round down to a ‘+5’ rating, which Cook does not do, as we didn’t have sufficient data from the last decade about their decimal placing.)

Nonpartisan redistricting leads to more competitive districts and less polarization, because officeholders will need to establish an ability to listen and bring people together to hold on to districts that could readily flip back and forth. That’s good for the country. It’s also good for Democrats, because its expansion could help reduce the percentage of swing seats Democrats must win to take back the House — currently at 69% with today’s maps.

But it won’t solve all of Democrats’ problems. Three out of five swing seats are currently controlled by House Republicans. To win those, Democrats also need a platform, narrative, and strategy that will allow them to connect with voters in every part of the country if they want to actualize some of these gains in the House.

Three out of five swing seats are currently controlled by House Republicans. To win those, Democrats also need a platform, narrative, and strategy that will allow them to connect with voters in every part of the country.

In an era of increasing political polarization, nonpartisan redistricting is making some headway toward competitive elections in naturally occurring ideologically and politically diverse communities. It may even help Democrats develop new strategies to win in the current batch of swing districts that are now mostly in Republican hands. That is what competition is intended to do and that’s why as painful as it may be for elected officials, nonpartisan district lines are necessary.


David de la Fuente is a Political Analyst at Third Way.