When democracies fail, they often do so gradually at the hands of elected leaders who enjoy robust support from voters, according to Milan Svolik, associate professor of political science at Yale.

In fact, since the 1990s, executive takeovers have surpassed military coups as the most frequent source of democratic collapse, he said.

Recent headlines provide examples. This month, Turkish citizens narrowly voted to substantially strengthen President Recep Tayyip Erdogan’s constitutional powers. In Venezuela, the democratically elected government, controlled by the party of the late Hugo Chavez, recently banned opposition leader Henrique Capriles from seeking elected office for 15 years, igniting protests and violent clashes. Russian President Vladimir Putin has cemented his power with overwhelming support from voters.

Svolik has studied this trend, focusing his recent work in Venezuela, where Chavez and his successor, Nicolas Maduro, have engaged in undemocratic behavior over 15 years. He conducted a survey to better understand why Venezuelans continue to re-elect leaders who subvert democracy.

Svolik discussed his research with YaleNews. An edited version of the conversation follows.

What questions were you seeking to answer in Venezuela?

The survey tested the following proposition: Voters are willing to trade off democratic principles for their political and economic interests. The broader intuition is that the more strongly that partisanship and economic interests are associated with one candidate, the more willing voters are to accept that candidate’s undemocratic behavior and still vote for him or her. They are willing to tolerate undemocratic behavior because that candidate, as opposed to competing candidates, better represents their partisan interests.

If voters are really willing to do this, then polarized societies are especially dangerous for democracies. This scenario fits several countries, including Venezuela, Turkey, and to a lesser degree, the United States, which have seen increased levels of polarization in recent years.

We often presume that ordinary people, or the masses, have pro-democratic instincts and serve as a pro-democratic check against the authoritarian tendencies of their elected leaders. If that’s true, then how come voters in Venezuela, who must see that Hugo Chavez and now Nicolas Maduro have been behaving undemocratically, nonetheless support them in large numbers? We need to understand why that has happened.

What makes Venezuela a suitable place to test this proposition?

It was ideal. Effectively, polarization has been increasing in Venezuela since Chavez came to power in 2002. Undemocratic behavior has been occurring, but not to the extent that, as a researcher, I’d be worried that people would be afraid to express their views.

There has not necessarily been outright electoral fraud in Venezuela, but the government has made efforts to manipulate the electoral process before elections. The main opposition figure was recently barred from running for office for 15 years. What is interesting about this conceptually is that Venezuelan voters can observe this undemocratic behavior. If the incumbent arrests a journalist or bans a TV station for criticizing the government, then voters know about it, and, crucially, the incumbent’s supporters are aware of it.

This raises an interesting question: Voters in a democracy can reject undemocratic incumbents by simply voting them out of office without resorting to protests or violence. Why don’t they do that? Why do voters who profess pro-democracy values — as most voters in Venezuela do — support incumbents who behave undemocratically?

How did you perform your research?

I conducted a representative survey of voters that presented participants a choice between two candidates. The candidates differed in a number of dimensions — I included silly things like their favorite sports — but I was only interested in two key dimensions: The candidates’ economic platforms and their proposals for reforming the political system, which were intentionally phrased as either pro or anti democratic.

I didn’t use these labels, but I wanted voters to see where each candidate stood economically and also their proposals to change the political system. These choices were designed in such a way that I could figure out whether a particular voter, because they’re a strong partisan, might be making a tradeoff and sacrificing pro-democratic policy shifts in favor of electing someone who behaves undemocratically but suits their partisan interests.

What did you learn?

A majority of respondents were unwilling to say that they would vote against an anti-democratic candidate when doing so would betray their economic interests.

Systematically, the more extreme people were when it came to partisanship, the more likely they were to stick with the candidate who best represented their political leanings regardless of the candidate’s undemocratic proposals. They were simply unwilling to sacrifice their partisan or economic interests for democracy.

This was strongest in the case of leftists in Venezuela but that might be somewhat moderated or influenced by the fact that the left has held power since 2002 and has been behaving undemocratically. To put it differently, if you’re on the right in Venezuela, it’s easier to be pro-democratic because it is in your economic interest to replace the incumbent.

Voters who were indifferent between left and right — moderates, basically — were more willing vote against their economic interests to punish an anti-democratic candidate.

What’s the key takeaway?

I think this is the experiment has the strongest bite in understanding the reasoning of the supporters of the non-democratic incumbent. The experiment mirrors what would be a costly behavior for them — betraying their incumbent, and potentially sacrificing their economic interests, to vote for a challenger with a pro-democratic bearing. It showed that most people were unwilling to do this.

This gets to how realistic we can be about the idea that the masses can serve as a check on undemocratic behavior by incumbents when societies, while unified in the support of democracy, are divided along partisan lines. The finding is that partisanship may seriously compromise the ability of the public broadly to hold in check anti-democratic or authoritarian tendencies of incumbents.

What are the implications for the United States?

Donald Trump was the candidate who could reasonably be called illiberal, given some his behavior during the campaign, such as threatening to have his opponent put in jail. Here is the empirical question: Were there moderate Republicans, versus strong Republicans, in the 2016 election who voted for Hillary Clinton or abstained from voting because they objected to Trump’s illiberal tendencies? Can we draw a line that separates moderate Republicans from strong Republicans, who understand that Trump was not fully respecting democratic norms but voted for him anyway because they preferred him to Clinton?

One thing I can say for certain is that the levels of polarization in Venezuela dwarf the levels of polarization in the United States. In Venezuela, there are more people at the extreme left or right either supporting or rejecting the incumbent than there are moderates. This is not the case in the United States.

To fully answer this question, I’d have to conduct an experiment in the United States, and I am planning to do that. One key modifier is that Venezuela is a good case because journalists have been arrested there, people have been prosecuted for criticizing the government, and the opposition’s leader has been banned from running for office. These things are unimaginable in the U.S. I can’t propose to an American voter an experiment in which one candidate is promising to ban a competitor. That would seem silly.

Does a leader’s effectiveness influence polarization? Will an undemocratic leader retain support if their policies fail to improve the lives of their supporters?

In Venezuela, my survey showed that there are people on the left who supported Chavez but don’t identify as strongly with Maduro. I think, in part, it is because the economy has gotten worse under Maduro to the point where people are calling Venezuela a failing state.

According to some reports, Caracas is the most dangerous city in the world, which is a reflection of the economic crisis largely caused by falling oil prices. Chavez was lucky enough to preside over a period of high oil prices, which allowed him to implement many of the social programs that appeal to the poor. Maduro simply cannot do that.

Something similar might be happening in Turkey. Erdogan presided over an unprecedented period of economic growth. Since the global financial crisis and the Syrian civil war, the Turkish economy has been getting weaker. Will Erdogan be able to maintain his support despite a weak economy? It’s an interesting question.

What struck you about the recent constitutional referendum in which Turkish voters narrowly granted Erdogan significant additional powers?

Erdogan was hoping for 60% and barely got a majority. His government demonstrated a lot of undemocratic behavior, such as intimidating the opposition and using state resources to campaign while denying others access to the media. Despite these advantages, Erdogan’s side only captured 51% of the vote. One wonders how an even contest would have turned out.

Let’s say the margin of victory was 2%. If you think all of the manipulation that occurred before the referendum at minimum delivered an unfair vote share of at least 2% to Erdogan, then we must conclude that the opposition would have won a fair contest.

The same tradeoff dilemma that I’ve tried to highlight in Venezuela applies to Turkey. How many supporters of Erdogan saw that he was behaving undemocratically and therefore abstained or voted against the referendum? How many saw that it was unfair but decided to vote for him anyway? It would be interesting to know, and I’m planning a similar survey in Turkey.