Since his papacy began more than two years ago, Pope Francis has railed against inequality and emerged as a staunch champion of the poor. In February, he spoke out against low-wage work specifically, saying in a homily in Rome that not paying fair wages is a “very grave sin.”

Federal contract workers on Tuesday morning are hoping to capitalize on that sentiment as they strike ahead of the pontiff’s afternoon arrival in Washington, D.C.

Good Jobs Nation, a coalition of progressive groups, says that it expects about 750 federal contract workers to walk off their jobs on Tuesday morning and march to a church two blocks from the U.S. Capitol, where Pope Francis will become the first pontiff to address a joint session of Congress on Thursday. At the church, the coalition says Democratic presidential candidate Bernie Sanders—an advocate of a $15 per hour federal minimum wage—will address the workers. The Sanders campaign confirmed he will be there.

The organization has fought for higher pay for low-wage federal workers, including those employed at the U.S. Capitol, National Zoo, and Pentagon, whose pay is funded with taxpayer dollars. An executive order signed by President Barack Obama in February 2014 gave federal contract workers $10.10 per hour, but the group says that’s not enough.

Forty federal contract workers sent a letter requesting a meeting with the Pope during his visit earlier this month, telling him “that even though we serve the wealthy and the powerful in the Congress, we earn so little that we live in utter poverty.” Paco Fabian, a spokesman for Good Jobs Nation, said that the workers delivered the letter to the nuncio, the papal ambassador, in Washington, D.C., and the U.S. Conference of Catholic Bishops but have not received an official response.

The workers will not come in direct contact with Pope Francis or his procession on Tuesday; he does not arrive in Washington, D.C. until the late afternoon. Fabian says the workers wanted to welcome the Pope as close to his arrival as possible and security constraints kept them from demonstrating during his public appearances.