The 2018 election — and especially the election of former bartender and waitress Alexandria Ocasio-Cortez to Congress — has inspired a spate of stories about working-class candidates, with titles such as “It’s way too hard for working-class people to run for office”; “Running for office is really hard if you’re not a millionaire”; and “Want Congress to look more like the people it serves? Provide member housing, pay staff more.”

But what would actually put more working-class people in political office? I contacted Duke University professor Nicholas Carnes, author of the recently published book “The Cash Ceiling: Why Only the Rich Run for Office — and What We Can Do About It.” Here is a lightly edited version of our exchange.

JS: Let’s start with the book’s title. What is the “cash ceiling” and why does it matter?

NC: “The cash ceiling” is the set of obstacles that discourage working-class Americans — people employed in manual labor, service industry and clerical jobs — from running for political office. Working-class jobs make up over half of the American labor force, but working-class Americans hold less than 3 percent of the seats in the typical state legislature and less than 2 percent of the seats in Congress.

The cash ceiling is why. Working-class Americans often can’t shoulder the burdens associated with running. They can’t take time off work or lose out on income to run a campaign. And they’re often passed over by party and interest group leaders in favor of more traditional white-collar candidates.

JS: So it’s not just about fundraising, but other costs?

NC: Exactly. Reformers focus on how much candidates raise and spend on their campaigns. But for many qualified working-class Americans, the other costs associated with running are an even bigger deterrent.

Campaigning is like taking on a part- or full-time job. If you’re already working two jobs or just barely getting by, it’s out of the question for you to spend months doing unpaid work in the hopes of getting elected. And that’s true even in races where candidates typically don’t raise and spend much money.

JS: In the book, you write that there are a lot of misconceptions about this topic. What are some of the factors that don’t help explain the dearth of working-class political candidates?

NC: The two biggest misconceptions are that working-class Americans are unfit to be politicians and that voters prefer rich candidates. The first one is just a form of prejudice. There isn’t any evidence that working-class people make worse politicians, and they tend to do fine in office. Workers who become politicians win reelection at the same rate as other politicians, and towns and cities run by majority-working-class city councils have similar rates of population growth and financial health.

There’s no evidence for the second misconception, either. I show in “The Cash Ceiling” and in some of my earlier research with Noam Lupu that voters actually tend to like working-class candidates. They just don’t see working-class candidates on their ballots very often.

JS: So then what does help explain the shortage of working-class politicians?

NC: The answers are resources and recruitment. Working-class people are less likely to run because they can’t put their jobs and lives on hold to campaign, and because party and interest group leaders rarely support qualified workers.

JS: In this sense, the factors that explain the dearth of working-class candidates are different from the ones that explain the dearth of female candidates, right?

NC: Somewhat, yes. We know from research by Jennifer Lawless and Richard Fox that qualified women are less likely to run for office because they’re less likely to see themselves as qualified. But I haven’t found any evidence of an analogous social class gap in political ambition. In a national survey I conducted in 2015, qualified women (women who reported having the qualities voters and party leaders want in a politician) were less likely to see themselves as qualified. But in the same sample, there was no difference in political ambition between qualified working-class Americans and their white-collar counterparts.

JS: You argue that the “candidate recruitment industry” disadvantages potential working-class candidates. How so?

NC: Most people don’t just wake up and decide to run for office. Candidates are often encouraged and recruited by party leaders, interest groups, politicians, and other people in and around government. And these people who recruit new candidates tend to favor candidates from white-collar jobs. In data on local Democratic and Republican Party officials, for example, I find that when they recruit new talent, they overwhelmingly pass over working-class Americans.

JS: So why do the people who recruit new candidates favor people from white-collar jobs?

NC: Many of them worry that working-class candidates wouldn’t be good fundraisers, and I think there could be some truth to that. But overall the process is more social than strategic. The best predictors of whether party leaders recruit working-class candidates are whether they have working-class people on their executive boards and whether they have lower incomes themselves. When party leaders look for new talent, they often look to their own friends and acquaintances. And since most party officials are well off, they usually don’t have many working-class people in their social networks.

JS: In your chapter on reforms, you talk about “empty promises” — some popular reforms that you don’t think will help get more working-class people in politics. What are some examples?

NC: The “empty promises” that I write about are pay raises for politicians and publicly financed elections. If we don’t pay politicians enough, the story goes, only rich people will be able to afford to hold office. And if elections were publicly financed, more working-class people could afford to run.

But working-class people don’t run because they can’t afford to take time off to campaign, not because the salary for winners is too low. Raising salaries for politicians actually seems to make holding office more attractive to professionals, not the working class. Eric Hansen and I find that states that pay lawmakers higher salaries actually have fewer working-class candidates and officeholders.

Public financing doesn’t address the obstacles that keep working-class people out of office, either. In places that publicly finance elections, there hasn’t been an increase in working-class politicians, and working-class people don’t worry any less about the other burdens associated with campaigning.

JS: So are you opposed to raising elected officials’ salaries or to public financing for elections?

NC: No, those reforms might still have other benefits. But by themselves they won’t increase the representation of working-class people.

JS: What reforms could make a real difference?

NC: The most promising reforms address the unique challenges facing workers. When organizations recruit working-class candidates and help them make ends meet while campaigning, the results are extremely encouraging. The best example is the New Jersey AFL-CIO’s Labor Candidates Program for working-class citizens. Since the mid-90s, its trainees have had a 74 percent win rate, they’ve won in almost 1,000 elections, and they’ve gone on to have successful careers in politics.

If that model were combined with seed money programs or even “political scholarships” that help working-class people pay their personal expenses while running for office, the results could be transformative.

But for that to happen, big foundations and interest groups will have to broaden their focus beyond traditional pro-equality reforms like increasing voter turnout and regulating campaign donations and lobbying. They’ll also have to support programs that actually give working-class Americans a seat at the table in our government.