BOSTON – Fast-food workers demanded a minimum wage of $15 an hour during a strike held in 270 cities across the country on Tuesday, USA Today reports. The protest is the start of a 12-month-long strategy to flex the political muscle of 64 million minimum-wage employees.

The walkouts are the biggest since a series of rallies calling for higher pay and the right to unionize began in 2012, according to Fight for $15. Demonstrations took place in Boston, New York City, Philadelphia and other cities with workers from McDonald’s, Burger King and other quick-service restaurants, as well as home care, child care, farm, FedEx and nursing home minimum-wage employees.

The workers kept up the protests throughout the day, rallying in the mornings and marching to local city halls in the afternoon. Protestors also planned to congregate outside the Republican presidential debate in Milwaukee on Tuesday evening. The issue has been discussed by both Republican and Democratic presidential candidates, with most Republicans against a higher federal minimum wage, while the Democrats are in favor of raising it to either $12 an hour (Hillary Clinton) or $15 (Bernie Sanders and Martin O’Malley).

Already, the protests have seen success, with Los Angeles, San Francisco and Seattle all citing the demonstrations as the main impetus for upping their minimum wage to $15 an hour, plus McDonald’s, Target and Walmart also agreeing to a higher starting wage. Currently, 29 states and Washington, D.C., have higher minimum wages than the federal level of $7.25. New York is contemplating a $15 an hour minimum wage.