The union-backed movement that helped pressure Amazon into setting a $15-an-hour bottom wage for its workers last week has refocused its efforts on McDonald’s.

The organization leading the effort, Fight for $15, said Wednesday that it has set the goal of getting the fast food giant to set a $15 wage.

“Amazon is the second largest employer in the nation. The move to $15 will put more money in the pockets of 350,000 full time and seasonal employees and impact the entire economy," the group said in a statement. "Now imagine the impact when McDonald’s, the second largest private employer in the world, raises wages to $15."

The group has staged protests at McDonald’s locations in Los Angeles and at a McDonald’s Chicago headquarters in the last week. At the latter event Rep. Jan Schakowsky, D-Ill., was among those arrested.

Fight for $15 was one of the main groups pressuring Amazon on the issue, having enlisted Sen. Bernie Sanders, I-Vt., to the cause. Sanders hosted events at his office to hear stories from Amazon employees regarding their workplace conditions.

[Opinion: Amazon's pay raise may make some Amazon workers poorer]

Following Amazon’s announcement, Sanders said he would do the same regarding McDonald’s. “McDonald's made $5.1 billion in profits last year and rewarded wealthy shareholders with over $7.7 billion. Meanwhile, many McDonald's workers need food stamps, Medicaid and public housing to survive. That is unacceptable. McDonald's workers need $15 and a union,” he said in a tweet.

Fight For $15 is funded and run by the Service Employees International Union. Labor Department filings indicate that SEIU gave $3.8 million last year directly to Fight for $15 and a related group, the Fast Food Workers Committee. SEIU has long sought to organize the fast food industry.

According to the website, which tracks pay rates by major companies, the average wage rate for a McDonald's crew member or cashier is $8 an hour, not much higher than the current federal minimum wage of $7.25 an hour.

More than 90 percent of McDonald's restaurants are privately owned businesses that only rent out the corporate brand. The corporation has said it cannot set the wages at the franchisees. Only the local owners can do that.