Both major U.S. political parties regularly say they are committed to working-class Americans and often claim to be the party of the working class. Yet neither Democrats nor Republicans nominate many candidates who spent substantial time in working-class jobs.

That shortage matters. Research in the United States and other democracies suggests that when more people from working-class jobs hold office, safety net programs are more generous, business regulations are stronger, and worker protections are more robust. Working-class people can influence policy in other ways, but the limited number of former workers in elected office means working-class interests often receive less attention in political institutions around the world.

We study the causes and consequences of the shortage of politicians from working-class jobs. We define working-class jobs as manual labor jobs, such as construction work; service jobs, such as restaurant serving; and clerical jobs, such as receptionist positions. We do not include small-business owners or people in jobs that require extensive formal education. Instead, we focus on work that tends to offer employees little stability or security.

There are, of course, a small number of notable politicians who came from these occupations. U.S. Rep. Alexandria Ocasio-Cortez, a New York Democrat, was a bartender before entering politics. Troy Jackson, Maine’s Democratic Senate candidate, worked as a logger before becoming involved in state politics. Indiana state Sen. Jim Tomes, a Republican, worked as a truck driver and union steward. Outside the United States, examples include Stefan Löfven, the former prime minister of Sweden, and Luiz Inácio Lula da Silva, the president of Brazil.

Politicians with those backgrounds often receive outsized media attention. But overall, people from working-class jobs remain sharply underrepresented in political institutions.

The working class rarely holds office

By our count, about half of all Americans in the labor force have working-class jobs. Yet people whose last job before entering politics was a working-class job make up only about 1% of the average state legislature, regardless of party affiliation. The same is true in Congress.

The United States is not alone. Beginning in 2016, we worked with a team of researchers to collect data on 97 of the 103 democracies with populations above 300,000. Like the U.S., the average democracy draws just 2% of the members of its national legislature from people whose last job was in the working class.

Some observers blame the shortage of working-class lawmakers on features of American elections, including high campaign spending or the decline of labor unions. But even in countries such as Germany and Belgium, which provide public financing to candidates, or Finland, where most of the labor force is unionized, people from working-class jobs make up around 5% or less of the national legislature.

What keeps workers out of office?

There does not appear to be any deficiency among working-class Americans that explains why so few go on to hold office.

Working-class candidates tend to be about as qualified, in measurable ways, as white-collar professionals. They are about as interested in running for office and about as likely to win when they run.

Our new book, “Keeping Workers Off the Ballot,” shows that the main reason working-class Americans — and their counterparts around the world — remain out of elected office is that they so rarely run. Campaigning for any office at any level of government is personally burdensome. It takes time and energy, carries personal risks ranging from embarrassment to physical violence, and always has an uncertain outcome.

In surveys in the U.S. and other democracies, working-class people are significantly more likely than equally qualified professionals to say they cannot run for office because they are worried about taking time off work and being unable to pay their bills during months on the campaign trail.

That inequality is intensified by a second process. In elections everywhere, parties and interest groups play major roles in recruiting and supporting candidates. These gatekeepers understand that working-class people have a harder time running for office. As a result, party leaders — even those who care deeply about the working class — often pass over qualified workers and instead favor white-collar professionals whom they believe will find campaigning easier.

Reforms that could help workers

We believe there are ways to overcome the barriers that keep working-class people out of office.

In a report we wrote for the American Academy of Arts and Sciences, we outline several options. Some would help in the short term, such as candidate training programs or political scholarships aimed at working-class people. Some examples already exist, including the New Jersey AFL-CIO’s Labor Candidates School.

Other proposals, while perhaps less likely in the current political environment, could create longer-term pathways to office for working-class people. These include party or institutional quotas for people from working-class jobs, as well as randomly selected citizen juries that advise policymakers.

Without serious reform efforts that address the factors keeping workers off the ballot, our research suggests that working-class people will continue to make up only tiny fractions of elected officials in the U.S. and in democracies around the world.

Noam Lupu, Professor of Political Science, Vanderbilt University, and Nicholas Carnes, Professor of Public Policy and Political Science, Duke University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

This story was originally featured on Fortune.com