Several 2020 Democratic presidential candidates on Thursday blasted fast food giant McDonald’s for paying its workers substandard wages.

The White House hopefuls – including Bernie Sanders, Julian Castro, Bill de Blasio, and Jay Inslee – joined demonstrations by workers in 13 cities targeting the world’s most powerful restaurant chain over wages and working conditions.

The protesters and the presidential candidates called on the Chicago-headquartered company to pay workers a minimum wage of at least $15 per hour and take more aggressive action in confronting sexual harassment and assaults on workers.

Inslee ripped McDonald's CEO Steve Easterbrook, who made $15.9 million in 2018 and $21.8 million in 2017, for short-changing the company's workers.

"Those people who say there isn't enough money in these corporations to pay adequate wages ought to look at this particular corporation where the CEO last year made 2,100 times the median wage of working people for the company," Inslee said. The Washington Governor and 2020 Democratic hopeful joined a demonstration in front of McDonald's headquarter in Chicago. "That's unjust and unsustainable. You can't tell me it's right that you can't give people a raise when the CEO makes as much in one hour as the median worker makes in one year. That's got to change."

Sen. Bernie Sanders, who held a video forum with McDonald's workers Thursday, took to Twitter after his meeting to note that the retailer Amazon last year raised its minimum wage to $15 and questioned why McDonald's "a company that...paid its CEO $22 million – can’t also pay its workers a living wage.”

Kirsten Gillibrand also criticized McDonald's in a Dallas Morning-News op-ed. She wrote that it was "unacceptable" that a company as profitable as McDonald's "refuses to require franchisees to pay workers at least $15 an hour."

McDonald's did not directly respond to the criticism from the presidential candidates.

“McDonald’s Corporation does not control the wages franchisees pay in their own restaurants," the company said in a statement. "The average starting wage at corporate-owned restaurants exceeds $10 per hour, and we believe the average starting wage offered by those independent business owners is likely similar. Separately, McDonald’s recognizes the rights under the law of individual employees to choose to join – or choose not to join – labor organizations.”

Almost unanimous support

Nearly the entire Democratic field has endorsed raising the federal minimum wage – which currently sits at $7.25 per hour – to $15. California, Connecticut, Illinois, Maryland, Massachusetts, New Jersey, and New York, as well as the District of Columbia, all have passed laws requiring a $15 minimum wage be in place by 2025 or earlier. McDonald’s announced in March that the company will no longer lobby against minimum wage hikes at the state and federal level.

The White House hopefuls are showing their support for the low-wage laborers as each candidate tries to burnish his credentials as a champion for American workers left behind in a booming economy.

"We need to stand with workers now more than ever to demand fair pay, better working conditions, and the right to unionize,” said Julián Castro, who took part in a McDonald's protest in Durham Thursday.

New York City Mayor Bill de Blasio, who joined more than 100 protesters outside a McDonald's in Des Moines, noted that his city has proven a push to a $15 minimum wage can be done without disruption. Earlier this year, the lowest legal wage at most New York City companies that employ more than 10 workers rose by $2, to $15 an hour.

"My friends, we heard it from Republicans, we heard it from too many Democrats too: They said it would never happen," said de Blasio, who added that he and his campaign staff would not eat McDonald's until the company raises the minimum wage at restaurants to $15 per hour. "But we in New York had a different idea. And when I heard people say it couldn't happen, I had a different idea. I said, 'Lets prove it.' "

Sanders told McDonald's workers Thursday that if he's elected to the White House they can be assured that working people around the country will make a $15 per hour minimum wage.

"If elected president, trust me, every worker in this country will make at least $15 an hour and people will have the right to join unions," Sanders told the workers in a video conference forum.

The protests were organized by the group Fight for $15. The group was launched in 2012 by the Service Employees International Union to help non-union McDonald’s workers call for a hike in wages.

Sexual harassment lawsuits filed

Earlier this week, the Fight for $15, the American Civil Liberties Union and Time's Up Legal Defense Fund announced it was filing 25 new U.S. Equal Employment Opportunity Commission complaints and lawsuits over alleged sexual harassment and retaliation at McDonald’s restaurants.

Easterbrook in letters earlier this week to Sen. Tammy Duckworth, an Illinois Democrat, and "Top Chef" host and executive producer Padma Lakshmi wrote that the company started working last year with RAINN, a leading anti-sexual violence organization, to improve its policies to more clearly define sexual harassment to its employees.

The company has also started working with a third-party firm on how to spot and prevent sexual harassment, and 90 percent of its corporate and franchise operators and general managers have taken it.

"Together, we have enhanced our policy so that it more clearly informs employees of their rights, more clearly defines sexual harassment, discrimination and retaliation, and provides examples of what unacceptable behavior looks like," Easterbrook added.

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McDonald's will also soon roll out an anonymous complaint line for workers and front-line staff will start receiving training about harassment, unconscious bias and safety, according to Easterbrook.

Violence against workers

McDonald’s workers also say that the company has done too little to ensure safety of workers from violent behavior by customers. Employees have called police around the country more than 700 times over the last three years to report assaults or threats of violence, according to a new National Employment Law Project report published this week.

Workers at one McDonald’s restaurant in Chicago filed an OSHA complaint this week in which they alleged that they haven’t been properly trained or provided with proper security to deal with constant threats of violence at that restaurant. Employees at that restaurant have had to make more than 30 calls to 911 since November, including three different incidents involving threats by a person with a gun and two additional incidents where a person has been shot, according to the complaint filed by workers Maria Torres and Martin Ortega.

“We have asked the company to put policies and procedures in place to protect us from workplace violence,” Torres and Ortega said. “Despite the frequent incidence of workplace violence, our employer has done nothing to implement safety measures to protect us. Our employer must have a workplace violence prevention plan. It is not enough to call the police after a violent incident.”

As President Trump is able boast of the lowest unemployment rate in nearly 50 years, many in the Democratic field are pushing back that working people have been left behind as the stock market has flourished and big corporations rack up huge profits.

Sanders in his talk with McDonald's workers accused the fast food chain of paying its workers' "starvation wages."

"Nothing is ever given to working people," Sanders said. "The only time working people make gains is when they organize and when they stand up and they fight against the corporate greed that we see today that is destroying the lives of so many of our people."

Contributing: Kelsey Kremer and Kim Norvell in Des Moines