In this year’s presidential primaries, more than 57.6 million Americans went to the polls, slightly less than the 2008 all-time record. It remains to be seen if high primary turnout will translate to high general election turnout when Americans vote in less than a month.

In the 2012 presidential election, just 57.5% of eligible U.S. residents went to the polls. In a number of developed nations voter turnout rates exceed 70%.

24/7 Wall St. reviewed average voter turnout rates over the last four presidential election cycles in every U.S. state. Voter participation ranged from approximately three-quarters of eligible Minnesota residents, the highest nationwide, to half of eligible voters in Hawaii, the lowest voter turnout in the country.

31. Illinois

> Voter turnout: 63.0%
> 2012 winning candidate’s party: Democrat
> Pct. with bachelor’s degree: 32.9%
> Pct. workers paid hourly: 51.5%

Illinois’ voter participation rate was in line with that of the nation in each of the last two midterm elections and slightly below the national turnout in the 2008 and 2012 presidential elections. This might be surprising to some, given President Obama’s political history in the state. He served in the Illinois State Senate from 1997 through 2004, and then in the U.S. Congress as an Illinois senator from 2004 until his presidency.

It may actually be the president’s home field advantage — as well as the state’s Democratic leaning — that kept voter turnout so low in Illinois. Nearly 22% of those who did not vote in 2012 said they did not think their vote would matter, compared to 16.2% of U.S. non-voters who said the same.

One of the main predictors of voter turnout is whether the election is closely contested. When a candidate appears poised to run away with an election, turnout tends to be much lower. When polls appear to be heavily favoring one candidate, voters may feel they cannot make much of a difference. This election, however, is much more even. While recent general population polls show Democratic candidate Hillary Clinton gaining a slight lead on Republican candidate Donald Trump, the candidates were effectively neck and neck as recently as last month.

On the other hand, turnout may be lower in this election because of the candidates. One recent poll conducted by the Pew Research Center showed that about 40% of eligible voters said they had difficulty choosing between the two major party candidates because neither was worthy of the presidency.

A number of factors are likely driving differences in voter turnout at the state level. It appears that in states with high-profile primaries, such as New Hampshire and Iowa, voter turnout tends to be higher during presidential elections. Over the last four general elections, both states were in the top five for voter turnout.

The level of education of state residents also appears to be a relatively strong predictor of voter turnout. While there are a number of exceptions, states with higher college attainment rates tend to have greater voter participation. Of the 20 states with the lowest voter turnout, 16 have a bachelor’s attainment rate below the national share of 30.6% of adults.

Other democracies around the world typically hold elections on the weekend or declare election day a national holiday. Presidential elections in the United States, however, are held during the work day. For this reason, individuals living in poverty are far less likely to vote than higher income individuals, at least in part due to lack of flexibility in the workplace. On the state level, however, the share of workers employed hourly did not appear to be the greatest single factor in voter turnout.

To identify the states with the highest and lowest voter turnout rates, 24/7 Wall St. reviewed the average percentage in each state of voting-age citizens who cast a ballot in the past four presidential elections, as well as the percentage of votes for the Republican and Democratic nominees in each of these races. All voter turnout data came from the Current Population Survey (CPS), conducted by the U.S. Census Bureau every month. Also from the CPS, we examined the reasons people cited for not voting as well as average weekly wages per state and nationwide. The percentage of adults who have at least a bachelor’s degree and poverty rates came from the U.S Census Bureau’s 2014 American Community Survey (ACS). Unemployment rates came from the Bureau of Labor Statistics (BLS). The proportion of workers employed on an hourly basis also came from the Bureau of Labor Statistics.

Click here to see the voter participation rates of all 50 states.