Democratic U.S. Rep. Keith Ellison said he is "proud to stand" with fast-food workers protesting nationwide to demand a $15 minimum wage and the right to form a union.

Strikers gather Thursday in more than 100 cities, including Minneapolis, where Ellison joined workers in pre-dawn demonstrations.

A number of fast-food workers make close to the federal minimum wage of $7.25 an hour, or roughly $15,000 annually. Some say that is not a living wage, especially for workers who are supporting families.

"Thousands of fast food workers will be out in the street today, demanding a living wage and the right to organize," said Ellison, co-chair of the Congressional Progressive Caucus.

"They're doing it because they have families to feed and parents to look after. They're doing it because they have basic needs that can't be met at $7.25 an hour. They're standing for the possibility of a better future and an economy that works for all Americans, not just the wealthy few. I'm proud to stand with them."

The National Council of Chain Restaurants, an industry trade group, took issue with the protests, which led to arrests in several cities.

"There are millions of workers in the food retail industry who find personal satisfaction in their work and appreciate the opportunities provided by the restaurants that hire them," executive director Rob Green said in a statement. "The activities being coordinated, financed and facilitated by labor unions - desperate for new membership dues - accomplish absolutely nothing."

The strike comes just days after President Obama voiced his support for the movement at a Labor Day speech in Wisconsin.

"All across the country right now, there's a national movement going on made up of fast-food workers organizing to life wages so they can provide for their families with pride and dignity," Obama said.