Experts on Camera

Dr. Jan Leighley: The science of voter turnout

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Pollsters and analysts are still working to get a complete picture of who voted on Election Day, and how.

On Friday, November 4, 2022, SciLine interviewed: Dr. Jan Leighley, a professor of government at American University. She discussed topics including: how the availability of newer ways to vote, such as voting by mail and early voting, affect turnout; how voter turnout is affected by practices that make it easier to register, such as offering automatic, absentee, or same-day registration; how turnout differs among midterm elections (like this year), presidential elections, and special elections; how pollsters predict turnout; how we know how many people voted; how to understand the persistent gap between people’s intention to vote and actual turnout; and how individuals can make a plan to vote that they will actually follow—and to help others participate, too.

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JAN LEIGHLEY: My name is Jan Leighley. I’m professor of government at American University in the School of Public Affairs. My research interests focus on voter turnout, political participation, and racial and ethnic political behavior.


Interview with SciLine

How do pollsters predict voter turnout?


JAN LEIGHLEY: Pollsters predict voter turnout using a variety of means. They have extensive databases on past turnout behavior of citizens, and they use a lot of the past behavior of those individuals to predict what will happen in the current environment. They do a lot of polling—quick polls among their supporters about their intentions to vote, their enthusiasm about voting—and they connect those historical details with the current environments and attitudes of their potential voters to predict what voter turnout will look like.

How do we know after an election how many people ultimately voted?


JAN LEIGHLEY: It’s usually January by the time we really have a good sense of how many people voted, and there can be corrections to that. Now those are usually small corrections. But it takes a lot of people a lot of time even to ensure that that number is correct. On top of that, estimating voter turnout is even more complicated because voter turnout, that number, there’s no firm or obvious number. You can count up the number of ballots cast, but you need to have in some sense a denominator on that. You need to know how many people were eligible to vote—to divide—to have that number of the percentage of eligible citizens who voted. And that can take oftentimes until February or March until we have firm numbers that we continue to report as the official record.

How do newer forms of voting, such as early voting or mail-in voting, affect turnout?


JAN LEIGHLEY: The newer ways that citizens have to cast ballots provide a lot of options for them and might make it easier to vote, but it actually makes the—doesn’t make it easier to determine their effects on turnout. The assumption has always been: if we make it easier to vote using these methods, more people will vote. Most of our research suggests that the people who take advantage of these newer ways of voting would have voted anyways on Election Day if they weren’t able to vote in those other ways, and that’s called a substitution effect. What the original intention of those reforms was to get new people into the voting pool. And so, we have a little bit of evidence that under some circumstances, we can indeed increase turnout a bit by having those options available. And that is usually perhaps in the range of 2 percentage points or so. But it depends on what parties do. It depends on the competitiveness of elections and other factors unique to specific elections.


How do regulations around voter registration affect turnout?


JAN LEIGHLEY: Absentee options—especially if you can register for absentee and remain registered as absentee and be sent a ballot or receive a ballot to cast on Election Day for election day—that has historically had a substantial effect, but those laws have been in practice for a fairly long time. The newer types of registration do make it easier. And I’d say the ones that are most likely to have a substantial effect are those that move when you need to register closer to the actual Election Day.

How does turnout differ between midterm and presidential elections?


JAN LEIGHLEY: Presidential turnout is substantially higher than midterm elections, when members of Congress and a set of senators and governors might be up for re-election or election. And so, turnout in presidential elections, the turnout level, tends to be around 50 percent, depending on various circumstances associated with the election. Midterms are usually in the 30s. Again, depending on candidates, competitiveness, economic conditions, what the parties do to try to mobilize turnout.

Does higher turnout mean better representation of the voter population?


JAN LEIGHLEY: The turnout level, which is what we hear about the most, isn’t the only feature that’s important. The other feature is what 50 percent or 30 percent of voters who show up, who they are. And so, low turnout levels—like 30 percent, if you believe that’s low—that are nonetheless representative of all eligible voters, wouldn’t necessarily be a problem for representation and who is elected, if those 30 percent of voters were like that larger pool of everyone who’s eligible. And in fact, what we find in midterms compared to presidential is that one group, especially, and that is younger individuals, is especially underrepresented in midterms. So, the sense is younger individuals who are getting established as voters and figuring out how to vote and deciding whether it’s a priority, they vote far less in midterms than they do in presidential elections. And so, that’s a voice that isn’t heard perhaps as strongly as you might hope.

What drives the persistent gap between people’s intentions to vote and their actions?


JAN LEIGHLEY: I think voting is like a lot of things that we have good intentions to do, right? It takes time, it takes effort, it takes presence of mind and life is complicated. And oftentimes, the short-term immediate, right in front of our faces issues or problems or tasks take precedence.

What turnouts are you watching for during the 2022 midterms?


JAN LEIGHLEY: The age lack of representation in midterms is one that I’m watching. Political scientists have watched it, I think, and journalists and campaign consultants have watched it in about every election. It’s a standard news story. Will this be the year that youth turnout increases substantially? And the story with 2018 was—look how much I think youth turnout increased by perhaps 8 percent to 10 percent, something like that. And everyone was excited. But the thing was turnout of every group increased by about that much. So, youth didn’t do themselves any better off in terms of their relative presence as voters. So, that, I think, will be a perennial until we can develop a system to get younger individuals engaged in elections earlier than they typically do. I think the other things are the extent—we tend to talk about elections and turnout as kind of a horse race and polling numbers and what’s happening. I really want to see the different turnout levels, perhaps associated by groups that are engaged by different issues. So, the Supreme Court ruling on abortion—will that mobilize not just women, but will that mobilize individuals to be more likely to get to the midterms? That’s something that might hit youth, given their support for abortion options generally. And so, whether it’s abortion, whether it’s the role or the presence of election deniers being elected to positions that manage elections in—theoretically in a nonpartisan way. If that gets individuals in Michigan and Wisconsin and Arizona, if that is a bump to their turnout. It’s easy in these midterms to talk about overall turnout level, how many midterm ballots were cast overall. But these are, in many senses, local races. The state of Arizona has a very particular profile in terms of the issues and candidates at stake. And so, that might yield higher levels of turnout than perhaps in other states where there is less contention or interest or mobilization of voters.

How are reporters doing covering voter turnout issues?

[Posted November 4, 2022 | Download video]