Nonpartisan Blanket (Top-Two) Primaries: A Primer

Note: This post was motivated by Arizona Proposition 121, a ballot initiative that will change how Arizonans vote in primary elections. Though this blog’s main focus is economics, the branch of political science that studies elections, psephology, is a field that uses similar game theory and statistical methods to conduct research on electoral systems.

Before I dive into the analysis portion of this post, it is probably a good idea to explain what exactly a “nonpartisan blanket primary” is. Also known as a top-two primary or a qualifying primary, a nonpartisan blanket primary is way of selecting the top two candidates for the general election without using the standard Republican and Democratic closed primaries.

Let’s break down this terminology just to be as clear as possible. First, “nonpartisan” just means that the primary is not controlled by any political party and, importantly, the candidates standing for election have not necessarily been endorsed by any political party. Candidates are usually allowed to state a party preference, using around 16 characters, but that does not mean the specified party supports the candidate or that the candidate actually holds the views of that party.

This may sound like splitting hairs, but the difference between being endorsed by political parties and merely stating a party preference is the main reason the United States Supreme Court ruled nonpartisan blanket primaries to be constitutional in Washington State Grange v. Washington State Republican Party in 2008. Before this ruling, nonpartisan blanket primaries were considered unconstitutional because when candidates listed their party affiliation (n.b. this is distinct from stating a party preference), the political parties felt they were being forced to endorse candidates whom they might not actually support.

Next, “blanket” means that the primary consists of all the candidates running for a given elected office, regardless of political party. And finally, “primary” refers to the fact that this stage of the election process is used to winnow down the field before the general election. Generally, if no single candidate in the primary receives a majority of the votes, then the top-two vote getters will advance to a general election. It is also important to note that this type of primary is an “open” system, meaning that all registered voters are eligible to vote. This contrasts with closed primaries where only registered voters of a particular political party can vote. While not all Republican and Democratic primaries are closed, many of them are, which means independent voters are often excluded from a critical stage of the voting process.

Now that you understand what a nonpartisan blanket primary is (hopefully), I want to show you that, when structured properly, it is superior to our current primary system. First, what are the goals of a nonpartisan blanket primary? Proponents of this system contend that by including independent voters in the primary process, each party’s base will have less influence on who gets elected. They hope this more inclusive approach to elections will have a moderating effect on politicians and incentivize bipartisanship. According to DW-Nominate, a scaling method that uses congressional roll-call votes to measure polarization, the current congress is the most polarized it has been in decades. The video below shows how polarization has changed throughout the years.

In August of this year, the approval rating of Congress hit an all-time low of 10%, so it’s fair to assume that this level of polarization is not healthy for the institution in the long-run. With few examples to study, political scientists are still researching whether nonpartisan blanket primaries are effective in decreasing polarization. Since we lack hard data to back up the supporters of top-two primaries, let’s address the system’s critics. I dismiss out of hand the main criticism from incumbent politicians that the proposed change is an attack on political parties. That’s exactly what it’s supposed to be! Politicians view any change as a negative because they have been very successful playing by the rules as they are currently written.

There are, however, two genuine criticisms of nonpartisan blanket primaries. The first is that incumbents will be further entrenched because the “anti-incumbent” vote will be split among numerous challengers, meaning the incumbent will get a majority of the vote in the primary and will not have to compete in a runoff election (this is how Louisiana conducts its primaries). Fortunately, this one is easy to address: don’t do that. Even if a candidate gets a majority vote share, the top-two finishers in the primary should automatically advance to the general election, which is how Prop 121 is designed. Consider the case where an incumbent receives 51% of the vote in the primary and three challengers receive 17%, 16%, and 16% each. By not automatically ending the election because the incumbent got a majority share of the vote, the 17% challenger has 3 months to gain name recognition and create an anti-incumbent coalition. Come the general election, it is plausible that the outcome will be flipped on the incumbent congressman.

The second criticism is that nonpartisan blanket primaries incentivize political parties to only have two affiliated candidates contest a primary. Consider the case where two Republican-affiliated candidates each receive 20% of the vote and four Democratic-affiliated candidates each receive 15% of the vote. In this case, the two Republicans would advance to the general election and this liberal-leaning district would be robbed of a left-of-center choice. While there is an actual risk of this situation occurring, I think it would be a rare occurrence in an open system. When anyone can run in the primary and state a party preference, it will be difficult for party bosses to control the composition of the slate of candidates.

Lastly, there is a minor criticism that top-two primaries encourage strategic voting, i.e. members of political parties voting for weak candidates of the opposing party to increase their preferred candidate’s chances in the general election. Again, I think this criticism assumes far too much cooperation and coordination among thousands of people. The voting behavior of your fellow citizens is too unpredictable to incentivize that kind of voting strategy.

I hope this “primer” helped you understand how a nonpartisan blanket primary works, what its supporters hope it achieves, and why criticisms of the proposed changes are largely unfounded.