The Democratic Socialists of America (DSA) is a political organization in the United States and the country's largest socialist organization, with more than 90,000 members as of November 2025. A big tent of socialists on the left wing of the political spectrum, the organization is primarily organized around the principles of democratic socialism, with its members active in electoral politics, labor organizing, and direct action campaigns. DSA, which is not a political party with a ballot line, has a decentralized structure in which local chapters and ideological caucuses have significant autonomy. The organization's largest chapter is in New York City, where the organization is also headquartered.
DSA was formed in 1982 when the Democratic Socialist Organizing Committee (DSOC) and the New American Movement (NAM) merged. The merger was seen as a symbolic healing of the rift between the Old Left, represented by DSOC's social democrats and trade unionists, and the New Left, represented by NAM's activists who emerged from the social movements of the 1960s. Initially led by Michael Harrington, the organization functioned as a small advocacy group for its first three decades, continuing DSOC's strategy of "realignment" by working within the Democratic Party to push it to the left.