NEW YORK – Thousands of fast-food workers and their supporters beat drums, blew whistles and chanted slogans Thursday on picket lines in dozens of U.S. cities, marking the largest protest yet in their quest for higher wages.

The nationwide day of demonstrations came after similar actions organized by unions and community groups over the past several months. Workers are calling for the right to unionize without interference from employers and for pay of $15 an hour. That’s more than double the federal minimum wage of $7.25 an hour, or $15,000 more per year for full-time employees.

Thursday’s walkouts and protests reached about 60 cities, including New York, Chicago and Detroit, organizers said. But the turnout varied significantly, with some targeted restaurants seemingly operating normally and others temporarily unable to do business because they had too few employees.

Ryan Carter, a 29-year-old who bought a $1 cup of coffee at a New York McDonald’s where protesters gathered, said he “absolutely” supported the demand for higher wages.

“They work harder than the billionaires in this city,” he said. But Carter said he didn’t plan to stop his regular trips to McDonald’s.

Jobs in low-wage industries have led the economic recovery. Advocates for a higher minimum wage say that makes it crucial that the jobs pay enough for workers who support families.

The restaurant industry says it already operates on thin margins and insists that sharply higher wages would lead to steeper prices for customers and fewer opportunities for job seekers.

The drive for better pay comes as the White House, some members of Congress and economists seek to raise the federal minimum wage. But most proposals are for a more modest increase, with President Obama suggesting $9 an hour.

The Service Employees International Union, which represents more than 2 million workers in health care, janitorial and other industries, has been providing financial support and training for local organizers in the fast-food strikes around the country.

McDonald’s Corp. and Burger King Worldwide Inc. say they don’t make decisions about pay for the independent franchisees that operate the majority of their U.S. restaurants. At restaurants that McDonald’s owns, the company said, any move to raise entry-level pay would increase overall costs and lead to higher menu prices.