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Have We Fixed Political Polarization Yet?

A look at California's top-two primary system, which aims to correct one of the biggest imbalances in politics.
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The California State Capitol in Sacramento. (Photo: Franco Folini/Flickr)

The California State Capitol in Sacramento. (Photo: Franco Folini/Flickr)

Over the past decade or so, reformers have suggested a lot of ideas for ways to depolarize our political system. Indeed, in the political world, combating partisanship is one of the hottest industries right now. A good deal of this talk is just hot air, but a few states have actually experimented with new political systems to see if they affect partisanship. California, in particular, adopted a top-two primary system (all candidates of all parties compete against each other in the primary, and the top two vote-getters go to a runoff election in November, even if they're of the same party) in 2010, and we now have a few years of evidence to judge its effectiveness. So, how's it going?


It's a pretty mixed bag, really, but no results have been particularly strong. The California Journal of Politics and Policy produced a special issue on this topic earlier this year (and a related series of blog posts at Mischiefs of Faction). And I just reviewed two papers on this very topic at the State Politics and Policy Conference in Sacramento last week. So there's definitely some very strong scholarship focusing on this question.

If you can do away with legislative partisanship by changing the way parties nominate candidates, that's a pretty profound finding, and it points the way forward for other states.

And it's an important question! If you can do away with legislative partisanship by changing the way parties nominate candidates, that's a pretty profound finding, and it points the way forward for other states—and possibly the nation as a whole—as a way to create a more productive and harmonious political system. On the other hand, if you overhaul the way parties nominate candidates and it doesn't affect legislative partisanship at all, that's also a pretty profound finding. It would suggest that parties aren't all that affected by election rules or that they are very creative and adaptive to institutional rule changes.

At any rate, here's what we know so far. For one thing, according to some preliminary recent work by Boris Shor and Eric McGhee, there just hasn't been an overall change in legislative polarization in California under the top-two system. The state legislature there, already the most polarized in the nation, has remained just as polarized in recent years.

Now, there may be some more subtle effects. There's at least some evidence that legislators elected under the top-two system are becoming better representatives of their districts. That's not nothing. Also, there's a bit of evidence that California's Democratic politicians (although not Republicans) moderated a bit after 2012, but that's probably more due to redistricting, which occurred simultaneously to the top-two system's implementation.

In another conference paper, Christian Grose looked at the campaigning behavior of legislators across a wide range of states, including California. He conducted an experiment to see whether candidates for office would respond to an email from someone of their same party, someone from a different party, or an independent. While the findings are preliminary, they are intriguing: Candidates from top-two systems were more likely than those in other systems to respond to voters from outside their party, even in the general runoff election. This is a potentially very encouraging finding for reformers. Even if the top-two system doesn't lead immediately to depolarization, it may make politicians more willing to engage voters outside of their party and listen to a wider range of ideas.

But one of the main takeaways from all this research is that there just aren't a lot of aggregate findings pointing to depolarization. What we do see, rather, is a few key races where they top-two system made a big difference. In a recent special election to California's 7th Senate district, for example, moderate Democrat Steve Glazer prevailed over more liberal Democrat Susan Bonilla in a pretty liberal district. Under California's previous closed primary system, someone like Bonilla likely would have handily defeated a Republican challenger. But under the top-two system, Glazer had the incentive to assemble a coalition of moderate Democrats, independents, and Republican voters. There are not very many races like this one, but they do happen now.

That may end up being the top-two system's most enduring legacy. For decades, moderate politicians in California have looked at the political system and largely concluded, "Why bother?" It just wasn't a system that allowed them to succeed. They couldn't raise money, they couldn't win votes, and no one would endorse them. But if moderates now have a shot some of the time, that incentivizes more of them to run for office, and it incentivizes donors and party elites to back such candidates.

If the top-two system really does succeed in undermining partisanship, that will likely be the way it happens. It won't happen overnight, but moderates might just get the impression that the Golden Gate is open to them.

What Makes Us Politic? is Seth Masket’s weekly column on politics and policy.