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.

11. Colorado

> Voter turnout: 66.6%
> 2012 winning candidate’s party: Democrat
> Pct. with bachelor’s degree: 39.2%
> Pct. workers paid hourly: 45.7%

Voter turnout has increased in every presidential election in Colorado, from 57.2% participation in 2000 to 70.4% participation in the 2012 election. Of the last four elections, an average of 66.6% of eligible voters made it to the polls, a larger share than in the vast majority of states. Voter preferences in Colorado tend to match those of the country as a whole as the state went to Bush in 2000 and 2004 and to Obama in 2008 and 2012.

Last August, after the Republican Party officially ruled that state delegates must support the candidate that wins the caucus vote, Colorado forfeited its role in selecting the GOP’s presidential candidate. States that hold caucuses tend to have higher voter turnouts in general elections, and since it opted entirely out of the nomination process, Colorado’s participation rate may take a hit in 2016.

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.