PORTLAND, Ore. — It’s nearly as certain as Oregon’s rainy season. When there’s an election, voters in the state respond with an enthusiasm that’s rare in most places in America. They did it again this year.
Average voter turnout across the country was horrible during this year’s midterms: About a third of those eligible to cast ballots did so, according to an Associated Press tabulation of preliminary data from local officials and state election authorities. That’s the lowest turnout in at least five decades.
But turnout surpassed 50 percent in a handful of states: Maine, Wisconsin, Colorado, Alaska, Minnesota and Oregon.
During each election over the past 10 years, these states have often been among the top performers.
Trying to explain the phenomenon can be elusive. Each state is different — some lean Republican, some lean Democrat, for example — and experts say there’s no precise equation that results in higher voter turnout.
A few things, though, tie Oregon to its fellow high-voter-turnout states: A century-old tradition of civic-mindedness that dates to the Progressive Era, convenient voting procedures and especially contentious races or ballot issues.
“There is something about our civic culture in this state that rewards civic participation of all kinds,” said Minnesota’s recently elected secretary of state, Steve Simon. “We are doers and joiners and voters in Minnesota.”
The states with consistently high turnout tend to make it easy to cast ballots. Colorado, Maine, Minnesota and Wisconsin allow voters to register on Election Day. Colorado, Oregon and Washington state allow voting by mail. Washington often has high turnout but was closer to the middle of the pack this year at 41 percent.
An especially contentious race or ballot issue also drives voters to weigh in. This year, several of the top voter-turnout states had closely watched races.
Wisconsin has long been a battleground state in presidential elections, and most recently, it has had a string of hotly contested campaigns after Republican Gov. Scott Walker’s push to weaken bargaining rights for public employee unions.
“People see their votes as making a difference,” said Kevin Kennedy, Wisconsin’s chief elections official. “The fact that it’s had a very sharp partisan divide the past few years probably focuses to engage voters.”
Maine’s turnout was boosted by contested races for governor and U.S. House, said Maine Secretary of State Matthew Dunlap.
Oregon voters turned out in droves to vote on a ballot measure asking whether they wanted to legalize recreational marijuana. It drew 40,000 more votes than the hotly contested race for governor.
