NEW YORK (AP) — Protesters calling for pay of $15 an hour and a union will be at McDonald's stores around the country Thursday as part of an ongoing push targeting the world's biggest hamburger chain.

The "Fight for $15" campaign says low-wage workers plan to turn out to show their solidarity with fast-food workers. They say they're targeting McDonald's because of its ability to influence pay practices throughout the economy.

The push is being backed by the Service Employees International Union and began in late 2012, with fast-food workers in New York City. Since then, the campaign has expanded and helped turn low pay into a major political issue.

McDonald's said it invests in the future of its employees with programs that help them earn high school and college degrees.