The Democratic Socialists of America (DSA) is joining forces with major unions on a national campaign for worker rights. On March 7, DSA, the Communications Workers of America (CWA), and the International Union of Painters and Allied Trades (IUPAT) launched an effort with an ambitious goal: getting Congress to pass the Protecting the Right to Organize (PRO) Act. If signed into law, the legislation would be the most significant labor rights bill since the New Deal era.

Over the past month, thousands of volunteers and organizers representing both DSA and the unions have made over five hundred thousand phone calls to voters in key legislators’ home states, asking voters to tell their representatives to support the PRO Act. This month, DSA and the unions plan on escalating the campaign with in-person rallies and town halls.

The collaboration offers something new to both sides, organizers told me. Though individual DSA chapters have worked with IUPAT and CWA locals before, walking picket lines and providing strike support, collaborating with unions on the national level offers the organization the credibility of labor groups that are major representatives of the working class, something that has so far proved elusive for the socialist group.