Turnout in presidential elections tends to be around 50% to 60%, depending on various circumstances associated with the election. Midterms are usually in the 30% to 40% range. Again, depending on candidates, competitiveness, economic conditions and 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 whatever 50% or 30% of voters who do show up, who they are.

And so, low turnout levels – like 30%, if you believe that’s low – that are nonetheless representative of all eligible voters, wouldn’t necessarily be a problem for representation … if those 30% of voters were like that larger pool of everyone who’s eligible.

And, in fact, what we find in midterms compared to presidential elections is that one group – younger individuals – (are) especially underrepresented in midterms.

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.

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 past behavior to predict what will happen in the current environment. (The pollsters) connect those historical details with the current environments and attitudes of their potential voters to predict what voter turnout will look like.

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.

Watch the full interview to hear about voter turnout.

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This article is republished from The Conversation, an independent nonprofit news site dedicated to sharing ideas from academic experts. It was written by: Jan Leighley, American University School of Public Affairs. News from experts, from an independent nonprofit. Try our free newsletters.

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Jan Leighley received funding from Pew Research Center around 2010.