Fast-food workers and supporters organized by the Service Employees International Union protested outside a McDonald's restaurant in Los Angeles on Sept. 18. (Patrick T. Fallon/Bloomberg)

As union membership in the United States has hit historic lows, several thousand service industry workers will strike next week in seven states to demand union representation.

Workers at major fast-food chains will walk off the job between Oct. 2 and Oct. 4, in tandem with strikes and rallies by airport, hospital, child-care and higher education workers, to corral public and political support for unions ahead of the November election. The effort is being orchestrated by Fight for $15, the group that helped popularize the push for a $15-an-hour minimum wage,

“The systemic problem of being overworked and underpaid isn’t concentrated to just one job in America,” said Mary Kay Henry, president of the Service Employees International Union, which is backing the strikes. “People are losing patience when they see that the economy is booming but their lives aren’t getting better.”

Centered in cites in Michigan, Wisconsin, Illinois, Florida, Georgia, California and Connecticut, the strikes come at a pivotal moment in public attitudes toward unions: Last year, 10.7 percent of American workers were union members, the lowest since the 1930s, before the country had labor protection laws, according to a January report from the federal Bureau of Labor Statistics. But the number of nonunion American workers interested in joining unions is at a four-decade high, at 48 percent, according to a recent MIT survey.

Numerous studies, including a 2016 study from the Economic Policy Institute and a June study from Princeton economists, show unions historically helped cut down income inequality and suggest current wage gaps might be attributable to union declines.

Some of the strikes will be followed by door-to-door canvassing efforts in battleground states, where Fight for $15 members have been working with candidates and lawmakers to make it easier for workers to organize.

The striking employees — many of whom work for major fast-food chains, including McDonald’s, Wendy’s and Burger King — say union representation would help them fight for basic workplace protections they’ve been denied, such as benefits, vacation days and guaranteed schedules.

Adriana Alvarez, 26, has worked at a McDonald’s restaurant in Cicero, Ill., for eight years. She’s single and has a 6-year-old son. She struggles to explain to him why they struggle financially even though she works all the time. “I want to be able to take care of my son without worrying about losing a day of wages,” Alvarez said. “Some of my co-workers are scared to speak up about what happens to them because they’re scared of retaliation.”

Brittany Williamson, 24, has worked at a McDonald’s in Detroit for more than three years. She got involved in labor organization protests during her first week on the job, after a co-worker told her about a group fighting for higher wages. She’s been active ever since, she said, but hasn’t seen the kind of changes she thinks fast-food workers deserve. That’s why she’s striking next week, she said.

For all the talk about raising the minimum wage, Williamson said she thinks union representation is even more important. She said she and her co-workers have no way to advocate for themselves. For example, when her grandmother had a stroke recently, Williamson said, she couldn’t take time off to visit her in the hospital for fear of losing more hours or being fired. A union would help employees get time off for emergencies like that, she said.

Williamson added she and her co-workers live at the mercy of schedules that are hard to access and rarely available in advance. Even off the clock, their lives are dictated by work, she said.

“We’re not asking for too much,” Williamson said.