The fast food workers' movement is gaining momentum. Almost two years after they staged their first one-day strike in New York City, fast food workers are holding their seventh strike today, protesting in more than 100 U.S. cities, many refusing to budge, risking arrest.

As of mid-morning Thursday, 21 protestors outside a Times Square McDonald's (MCD) were arrested in New York City and 50 workers were arrested in Detroit as a result of their civil disobedience.

Related: Fast-food workers take to the streets demanding higher pay

"These are workers who are actually willing to put their jobs on the line to make clear they're working for a living but can't make a living from work," says Christine Owens, executive director of the National Employment Law Project, which promotes policies to boost job growth, economic mobility and enforce worker rights.

Fast food workers are striking for a wage of $15 an hour and the right to form a union. Many don't make earn much more than the federal minimum wage of $7.25 an hour, or about $15,000 a year for 40 hours a week -- below the official poverty level for a family of two or more.

Related: McDonald’s Should Share Billions in Profits With Fast Food Workers: Labor Organizer

While the federal government hasn't changed the minimum wage in several years, an increasing number of states and cities have. Twenty-three states and Washington, D.C. have minimum wages above the federal minimum. Seattle has raised its minimum wage to $15 an hour by 2018, Chicago to $13 by 2018 and San Diego to $11.50 by 2017.

Related: Low wage jobs dominate the U.S. economic recovery

These minimum wage increases plus fast food strikes "will exert pressure on Congress eventually to act" and raise the minimum wage, says Owens.

Earlier this year the CBO reported that an increase in the federal minimum wage to $10.10 an hour, which President Obama favors, would result in 500,000 less jobs but higher wages for about 16.5 million workers.

Owens discounts the argument that higher wages means job cuts and argues that higher wages help the economy because workers then have more money to spend.

"Most of the recent research suggests that if there is an impact on jobs it's a very minimal impact and that the benefits of raising wages far outweighs what may be a modest, if any, impact on jobs," she says. "The economy continues to struggle because of lack of demand and the reason for that lack of demand is that wages have been falling for 90% of workers over the past year. The only workers who actually saw increases were those in states that raised their minimum wages."

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