The Socialist Party of America was founded in 1901 and first ran a national campaign in 1904. Eugene V. Debs was the Socialist Party’s nominee for President and was on the ballot in Maryland in every election from 1904 to 1912. In 1916, Allan Benson represented the SPA on Maryland’s Presidential ballot. In 1920 Debs was nominated for a final time while he was in federal prison for violation of the Sedition Act, a victim of the first Red Scare. While Debs was an American and was merely incarcerated, many Socialist organizers were immigrants and were deported by the thousands, most with little or no due process.

In 1916, the Intercollegiate Socialist Society held a national conference near Annapolis. The ISS was a national student group founded by prominent Socialists including Clarence Darrow, Jack London, and Upton Sinclair, the Baltimore-born author of The Jungle who later ran as for Congress as the nominee of the Socialist Party. The ISS would later rename itself as the League for Industrial Democracy, and later its student wing the Student League for Industrial Democracy would rename itself Students for a Democratic Society (SDS), one of the most well-known and influential 1960s student groups.

One of the attendees of the 1916 conference was Elisabeth Gilman, daughter of the first President of Johns Hopkins University. Gilman was inspired by the conference and meetings with Socialists in Europe to join the Socialist Party of America. She helped found the precursor to the Maryland chapter of the ACLU, was active in the defense of Sacco and Vanzetti, and was nominated by the Socialist Party to run for Mayor of Baltimore in 1935. The Socialist Party had previously nominated C.F. Saunders for Mayor of Baltimore in 1915.

The Socialist Party regularly nominated candidates for Governor of Maryland - Silas Crabil in 1903, Ira Culp in 1907, Charles Devlin in 1915, Arthur Blessing in 1919, William Champlain in 1923, P. Gustav Dill in 1926, Elisabeth Gilman in 1930, Broadus Mitchell in 1934, and David Eyman in 1938.

In addition to her campaigns for Mayor and Governor, Elisabeth Gilman was nominated to run for United States Senate in 1934 and 1938. Gilman was friends with Norman Thomas, a minister who was a Socialist Party leader and its six time nominee for President. He was on the ballot in Maryland five times from 1928-1940 (the Socialist Party endorsed the Progressive candidate Robert La Follette in 1924), and again in 1948.

Darlington Hoopes followed Thomas as the Socialist Party’s nominee for President in 1952 and 1956. Hoopes was born in Bel Air, Maryland.

During Hoopes’ campaigns, the second Red Scare decimated many activist and political groups, and the Socialist Party did not run a candidate for President again for twenty years. In 1972 the Socialist Party of America met for the final time, where it split into three entities. One of the three – the Socialist Party USA – grew out of the ‘Debs Caucus’, a group of SPA members committed to returning to the Socialist tradition of running candidates independently of the existing capitalist parties. The SPUSA began running candidates again in 1976 and continues today to build an anti-capitalist, worker-run party contesting elections on all levels. In 1980 the Socialist Party USA established the Socialist National Committee, one of a handful of political parties authorized by the Federal Election Commission to organize on the national level.