Fast food workers in seven states, including Michigan, continued their campaign to garner higher wages Wednesday by protesting outside several eateries.

Workers are asking to be paid a minimum of $15 an hour and the right to organize without retaliation.

The campaign, organized by a coalition of labor, community and clergy groups called Fast Food Forward, has been building momentum since last fall, when the protests first came into the national spotlight.

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Currently, the median pay for the nearly 50,000 fast food workers in New York City is $9 an hour, or $18,500 a year, according to the New York Labor Department. That's about $4,500 lower than Census Bureau's poverty income threshold level of $23,000 for a family of four. While minimum wage in New York is $7.25 an hour, food service workers may earn $4.65 an hour because their total compensation includes expected tips.

In May, the New York State attorney general's office said it was investigating whether fast food restaurant owners have cheated their workers out of wages by paying them less than minimum wage, not paying overtime and not reimbursing for work-related expenses like uniforms or gas for deliveries.

The investigation came on the heels of a study released by Fast Food Forward based on 500 interviews with New York fast food workers from McDonald's, Burger King, Wendy's and Papa John's. Nearly 85 percent of those surveyed said their employer had committed at least one form of wage theft.

Labor experts say there have been scattered attempts to organize over the last several decades, but very little in the fast food industry has stuck. Many say that's because there is a high turnover rate of labor in the industry.