Don't accuse this year's nonvoters of a moral defect, University of Minnesota political scientist Larry Jacobs counseled as we were talking turnout in the Nov. 4 election.

"It's a big mistake to treat turnout as an individual choice and to assign moralistic labels to those who fail to turn out, like 'lazy' or 'ignorant,' " the professor instructed. The reality is more complicated. "Personal habits of citizenship are just a small part of what influences turnout."

I was glad to hear it.

The usual American turnout pattern in nonpresidential elections has a definite partisan slant. The midterm vote compared with the presidential election showing is generally down a little for Republicans and a lot for Democrats. Why is that?

Years of covering Minnesota's two big political tribes have shown me that they are similarly devoted to democracy and equally susceptible to moral failings and character flaws. I have a hard time believing that the midterm turnout tilt happens because Democratic voters are more casual in their concern for this state and country, or that Republicans are by nature a more dutiful lot.

My unschooled quest for an answer was yielding more descriptions than explanations. Those deemed less likely to vote this year than in 2012 include African-Americans and Hispanics, Asian-Americans, unmarried women, young adults and people with annual incomes below $40,000. All were important components of President Obama's twice-winning majority coalition. All were scarcer at the vote in 2010, contributing to that year's GOP surge.

But knowing the color, gender, age and incomes of likely nonparticipants in this year's plebiscite wasn't enough. I asked the prof: Why would these people be disinclined to vote when the presidency is not on the ballot — more so than, say, your run-of-the-mill, 60-year-old, middle-class white male?

"That's a question that political scientists have been exploring for half a century and more," Jacobs said. They've determined that the mind-set that Americans acquire through formal schooling is part of the answer.

"I'm not talking about innate intelligence or devotion as a citizen. It's that as part of going to school and advancing in a career, you pick up certain skills and habits. Voting is one of them. The better educated you are, the more you're attuned to the importance of voting, and the more you're confident you can handle what is a pretty complicated voting system in America."

No other Western democratic nation makes voting as difficult as it is in the United States, Jacobs said. "We lead the world in excluding people."

In northern Europe, voter registration happens automatically at birth. In this country, registration requires proof of identity and residency. Just 10 states — Minnesota among them — allow voters to register on Election Day. Thirty-two states require a photo ID to vote. Minnesota would have been among them had a proposed constitutional amendment been approved in 2012. Most states deny the vote to felons at some point in the corrections process. Those restrictions disenfranchised 5.8 million Americans in 2012.

Complicated voting and educated habits aren't the whole story, Jacobs said.

There's something more concerning: A sizable share of Americans are deciding not to vote because they see little or nothing in it for themselves. "They're thinking, 'Why vote?' That's not an irrational question. The return on any one individual's vote is pretty small."

That may be so, if one sees oneself as one self. But identify with a group that's pushing an agenda in Congress or at the Legislature, and "why vote?" is easier to answer.

Take senior citizens, Jacobs said. Before the enactment of Social Security in 1935, their voter turnout matched that of other generational cohorts. Today they are the nation's most reliable voters. "They've got AARP informing them of how their stakes are being affected" by competing candidates' views about Social Security and Medicare. That motivates them to vote.

By comparison, "What government program and powerful organization supplies the motivation and resources for youth, lower-income people, less educated people and people of color to vote?"

Well, for starters and for students, there are Pell Grants, federally insured student loans and state support for public education. There's AmeriCorps and food stamps for the young people who work in that program for $1,000 a month and are forbidden to take a part-time job on the side. There's minimum wage, workplace rules, transit's availability, taxes … you get the idea.

But Jacobs reports that some of his students — in political science classes! — don't. They shrug and say they don't have time, or it's not a big deal, or "why vote?"

One might chalk up those attitudes to the misplaced priorities of youth. But one would also have ample reason to wonder whether a democracy in which half or more of its citizens refuse to vote can sustain that system for long. Nationally, turnout in the last midterm election was 41 percent.

The tendency of college students to shrug off nonpresidential elections has a lot to do with the political life story of state Rep. David Bly, DFL-Northfield, who is on the state House ballot this year for the fifth time. He won by 60 votes in 2006, lost by 37 votes in 2010, and won by comfortable margins in presidential years 2008 and 2012 — when turnout was 20 to 25 percent higher than it was for his squeaker midterm elections. In one St. Olaf precinct I checked, the vote total drop in 2010 from 2008 was 45 percent.

This being another midterm, it occurred to me that Bly may have moved into a Carleton or St. Olaf dorm, the better to lead get-out-the-vote activities on the campuses. While he hasn't gone that far, he acknowledged that he's been spending "a fair amount of time" on the campuses, in hopes of becoming a known name and face to students.

"I've learned that if college students don't know me, they won't vote in my race. They don't pay attention to state representative races," Bly said. "I've been getting to know students, talking about issues they care about, being involved in campus events." He'll learn on Nov. 4 whether that effort has paid off.

Bly is a mild-mannered fellow. Though he's a former teacher, he doesn't seem the type to give nonvoting students a professorial scowl.

But I bet Jacobs can muster a good one — like the one he rehearsed for me: "When a student tells me he doesn't have time to vote, I say, 'Then you wonder why Congress doesn't lower the interest rates on student loans. If you don't show up, don't expect your lawmakers to help you.' "

Lori Sturdevant is an editorial writer and columnist. She is at lsturdevant@startribune.com.