From Atlantic Cities:

The U.S. electorate isn’t entirely represented by the people in the U.S. who vote. Women are more likely to vote than men. Until the 2012 presidential election, whites were significantly more likely to vote than all minority groups. On the whole, Americans are more likely to vote the more education they have, the more money they earn, and the older they are.

This means that the people who participate in U.S. elections don’t necessarily mirror the interests of all Americans who ought to be eligible to vote. And one segment of the population stands out as disproportionately unrepresented: the disadvantaged.

It’s impossible to say if we’d elect different politicians, who’d try different policies, if more low-income parents and GED holders and minimum-wage workers voted. But there’s an interesting theory about this contained in a new book from political scientists Jan E. Leighley and Jonathan Nagler. They looked at voter turnout going back to 1972 in the book, Who Votes Now? Demographics, Issues, Inequality, and Turnout in the United States. Dan Balz has a good review of it here.

If inequality has grown worse over the last four decades, they ask, why hasn’t political momentum to do something about it kept pace with the scale of the problem? One potential piece of the answer is that the people most impacted by inequality are among the least likely to vote.

Leighley and Nagler also note that low-income and less-educated Americans are less likely to perceive differences between two candidates, suggesting that they’re not following campaigns in the same way as other would-be voters.

But why would this be? And can we do anything to boost voting among this group? (This second question goes beyond eradicating voter suppression tactics.) Two sets of research come to mind. One study concluded that grueling commutes seemed to sap people of the will to care about politics, with the perverse consequence that low-income people who often have the worst commutes are further distanced from the civic arena where they might complain about it.

The other research, from outside the political science field, revealed how the everyday challenges of poverty tax the brain so much that poor people are left with less mental capacity to worry about things the rest of us think about with ease. So a stressed single mother forgets to pay a bill on time. A low-wage worker preoccupied by making his rent can devote little energy to succeeding at night school.

Researchers Sendhil Mullainathan and Eldar Shafir never get into the implications of this for politics or democracy in their book about this work, Scarcity. But it seems entirely plausible that a poor parent who has to figure out how to produce dinner on $3 a day doesn’t have the bandwidth leftover to weigh the pros and cons of Chris Christie.

This doesn’t mean that low-income people as a group are uninterested in politics. Maybe the obstacle is not primarily about “interest,” or even time, or access to a ride to the polling place. If we want to think about increasing turnout among voters whose voices typically go unheard, maybe we ought to think about what else is consuming their attention instead.