Study: Medicaid expansion popular among college graduates. Does education foster empathy? A college degree is strongly associated with support for Medicaid. That helps explain why conservative states are voting to expand a safety net program.

David Matsa | Opinion contributor

Voters in Idaho, Nebraska and Utah tend to skew conservative politically, and the last time they supported a Democratic president was in 1964. Yet on Nov. 6, voters in all three states passed Medicaid expansion referendums after their governments failed to act. To succeed, these referendums needed a key voting bloc to look past its self-interest: college graduates with bachelor’s degrees.

The key to understanding the passage of these initiatives lies in the results of a similar referendum a year ago in Maine, which was the first state in the union to consider Medicaid expansion by popular vote. In research that will appear next year in the Journal of Health Politics, Policy and Law, I and Amalia Miller of the University of Virginia explored who voted in favor of Medicaid expansion in Maine. Because there was no exit polling, we examined local area voting results and Census information. We found that the expansion drew the most support in areas where a significant portion of residents had four-year degrees.

The association is shown in this figure, where each circle represents a locality in Maine, sized to reflect the number of votes cast. The vote share for Medicaid expansion is plotted against the share of the population with a bachelor’s degree. College education has a strong, positive association with voting in favor of Medicaid.

Medicaid expansion has been in the hands of each state since a landmark 2012 Supreme Court ruling that upheld the Affordable Care Act as federal law, but it left the decision to expand Medicaid to individual states. Most legislatures have approved or rejected Medicaid expansion along party lines. A recent example is in Virginia, where election of a Democratic majority in the legislature was soon followed by Medicaid expansion in that state.

But politicians are elected on the basis of their positions on a range of issues, and so voters elect legislators who don’t necessarily agree with them on everything. By putting Medicaid expansion on the ballot, voters can express their will on this issue in isolation from other debates in partisan politics.

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Opinion polls have found correlations between stated opinions about Medicaid expansion and individual characteristics such as race, party affiliation and Medicaid receipt. We found similar patterns in the results of Maine’s referendum, with groups standing to benefit personally from expansion voting in favor, as you would expect: low-income individuals who would gain eligibility for benefits and the employees of hospitals, which profit from expansion because they are required to provide care to patients in emergency situations regardless of their ability to pay.

Consistent with their self-interest, those with high incomes without bachelor’s degrees tended to vote against.

But why would college-educated voters want to expand a safety net meant for low-income and poverty-level individuals?

Presumably, those with four-year degrees would not likely personally need the Medicaid expansion that allows more low-income people — specifically nondisabled, nonelderly adults with no children — to qualify for benefits. Support from these voters speaks largely to selflessness, to support a measure that creates a cost but benefits others.

Does more education foster more empathy?

Our analysis of voter behavior in Maine found that college graduates with humanities degrees were the most supportive of Medicaid expansion. People with science and engineering degrees also tended to vote in favor.

In contrast, business majors were more likely to oppose it. Business majors might more often be Republicans, but general party support does not explain these sizable differences. Controlling for political party affiliation, the split between humanities and business majors remains.

The larger question is whether more education actually fosters more empathy. Is this principle also applicable more broadly? Ballot initiatives on raising the minimum wage could be a fertile area of study; voters have approved a dozen in the past five years, including two this month in Missouri and Arkansas.

Such research could give us clues about the social impact of direct democracy.

David Matsa is a professor of finance at Kellogg School of Management at Northwestern University.