A new coalition of labor groups is organizing low-wage workers and generating considerable attention from government officials.

In two months, the Good Jobs Nation coalition has used aggressive tactics — from employee walkouts to civil disobedience — to demand better pay for service employees working for vendors in federal buildings.

Last week, it filed a complaint with the Labor Department alleging wage theft by food vendors, claiming that eight franchises operating at the Ronald Reagan Building and International Trade Center have paid employees less than the minimum wage and ignored rules on overtime pay.

The Labor Department is investigating the allegations, an agency spokesperson said.

Congressional lawmakers and members of the D.C. Council have called on President Obama to address the situation.

On Tuesday, during another day of demonstrations, Good Jobs Nation hand-delivered its Labor complaint to Dan Tangherlini, head of the General Services Administration, who promised to meet to discuss the matter.

Workers who attended Tuesday’s demonstrations, many of them immigrants, said their employers have taken advantage of them.

“Just because we’re from the lower class doesn’t mean we don’t have rights,” said Cecelia Hernandez, a 22-year-old D.C. resident who works at Subway in the Reagan Building.

The D.C. Council is scheduled to vote Monday on a resolution calling on the president to “take all necessary actions” to ensure that the private employers pay wages high enough to support workers and their families without public assistance. Eleven of the council’s 13 members have sponsored or co-sponsored the proposal.

Two council members, Tommy Wells (D-Ward 6) and Kenyan R. McDuffie (D-Ward 5), spoke Tuesday at a rally in front of the John A. Wilson Building.

“The gap between the haves and have-nots has grown far too wide,” said Wells, who is running for mayor. “The federal government is the number one employer in the District and shouldn’t be using our tax dollars to pay its employees anything less than a living wage.”

Seventeen members of the Congressional Progressive Caucus also wrote to Obama on Tuesday echoing those concerns. They said the federal government “washes its hands of these workers, leaving them with exploitative wages.”

The letter asked Obama to form a working group that could develop new contracting guidelines to promote higher wages, but it stopped short of explicitly calling for an executive order or an increase in the minimum wage.

The White House did not respond to a request for comment.

The Good Jobs coalition said it represents the interests of more than 2 million low-wage employees who work for government contractors — doing everything from greeting visitors and selling memorabilia to driving trucks and making military uniforms.

The group formed about six months ago as a coalition of like-minded labor groups. Its funding comes largely from unions, including the Service Employees International Union, the International Brotherhood of Teamsters, the United Farm Workers and the United Food and Commercial Workers, according to organizers.

The group held its first demonstration in May, when service workers at federal buildings walked off the job to protest their wages.

“We saw an opportunity to hold our political leaders to set a standard and be a leader in creating good jobs,” said Corey Taylor, executive director of OUR D.C., one of at least six organizations involved in the coalition.

The coalition also includes the Samuel DeWitt Proctor Conference, the Employment Justice Center, Interfaith Worker Justice, Jobs With Justice and Restaurant Opportunities Center D.C.

Free-market advocates have contested the “living wage” movement, arguing that artificially raising the lowest allowable pay rate could increase unemployment. They say the market should determine compensation.

“If the government comes in, then it’s subjected to all sorts of pressure,” said Daniel J. Mitchell, an economist with the Cato Institute. “Unions will try to force the wages too high, and companies will try to force them too low. I’d rather let this be determined by voluntary actions between employers and employees.”

Trade Center Management Associates, which manages the Reagan Building, said in a statement last week that it will take appropriate action if the department determines that food vendors in the facility have violated federal guidelines.

The GSA said Tuesday that it wrote to the firm reiterating that it must follow federal and local laws in its contracts with federal food-court tenants. “GSA has clear guidelines in our contracts to ensure that our contractors follow the law, and we take allegations of violations very seriously,” the agency said.