In 1901 the Social Democratic Party (SDP) merged with Socialist Labor Party to form the Socialist Party of America. Leading figures in this party included Eugene Debs, Victor Berger, Ella Reeve Bloor, Emil Seidel, Daniel De Leon, Philip Randolph, Chandler Owen, William Z. Foster, Abraham Cahan, Sidney Hillman, Morris Hillquit, John Spargo, Walter Reuther, Bill Haywood, Margaret Sanger, Florence Kelley, Rose Pastor Stokes, Mary White Ovington, Helen Keller, Inez Milholland, Floyd Dell, William Du Bois, Hubert Harrison, Upton Sinclair, Agnes Smedley, Victor Berger, Robert Hunter, George Herron, Kate Richards O'Hare, Helen Keller, Claude McKay, Sinclair Lewis, Daniel Hoan, Frank Zeidler, Max Eastman, Bayard Rustin, James Larkin, Louis Waldman, Meyer London, William Walling and Jack London.
In the 1904 Presidential Election it was decided that Eugene Debs should be the Socialist Party of America candidate. His running-mate was Benjamin Hanford. Debs finished third to Theodore Roosevelt with 402,810 votes. This was an impressive performance and in the 1908 Presidential Election he managed to increase his vote to 420,793.
During this period Eugene Debs led the campaign for the release of William Haywood and Charles Moyer: "There have been twenty years of revolutionary education, agitation, and organization since the Haymarket tragedy, and if an attempt is made to repeat it, there will be a revolution and I will do all in my power to precipitate it. If they attempt to murder Moyer, Haywood, and their brothers, a million revolutionists at least will meet them with guns."
Between 1901 and 1912 membership of the Socialist Party of America grew from 13,000 to 118,000 and its journal Appeal to Reason was selling 500,000 copies a week. This provided a great platform for Eugene Debs and his running-mate, Emil Seidel, in the 1912 Presidential Election. During the campaign Debs explained why people should vote for him: "You must either vote for or against your own material interests as a wealth producer; there is no political purgatory in this nation of ours, despite the desperate efforts of so-called Progressive capitalists politicians to establish one. Socialism alone represents the material heaven of plenty for those who toil and the Socialist Party alone offers the political means for attaining that heaven of economic plenty which the toil of the workers of the world provides in unceasing and measureless flow. Capitalism represents the material hell of want and pinching poverty of degradation and prostitution for those who toil and in which you now exist, and each and every political party, other than the Socialist Party, stands for the perpetuation of the economic hell of capitalism. For the first time in all history you who toil possess the power to peacefully better your own condition. The little slip of paper which you hold in your hand on election day is more potent than all the armies of all the kings of earth."
Eugene Debs and Emil Seidel won 901,551 votes (6.0%). This was the most impressive showing of any socialist candidate in the history of the United States. In some states the vote was much higher: Oklahoma (16.6), Nevada (16.5), Montana (13.6), Washington (12.9), California (12.2) and Idaho (11.5).
Eugene Debs had developed a very strong following in America. The journalist, Max Eastman, wrote: "Debs was a poet, and more gifted of poetry in private speech than in public oratory. He was the sweetest strong man I ever saw. There is both fighting and love in American socialism, and Debs knew how to fight. But that was not his genius. His genius was for love, the ancient real love, the miracle love that really identifies itself with the needs and wishes of others. That gave him more power than was possessed by many who were better versed in the subtleties of politics and oratory."
The party contained both moderate and radical socialists. Eventually, in 1912 Victor Berger and Morris Hillquit, the leaders of the right-wing, gained control and expelled the left-wing led by Bill Haywood.
On the outbreak of the First World War most socialists in the United States were opposed to the conflict. They argued that the war had been caused by the imperialist competitive system and argued that the America should remain neutral. This was also the view expressed in the three main socialist journals, Appeal to Reason, The Masses and The Call.
In an article in September 1915 Eugene Debs wrote: "I am not opposed to all war, nor am I opposed to fighting under all circumstances, and any declaration to the contrary would disqualify me as a revolutionist. When I say I am opposed to war I mean ruling class war, for the ruling class is the only class that makes war. It matters not to me whether this war be offensive or defensive, or what other lying excuse may be invented for it, I am opposed to it, and I would be shot for treason before I would enter such a war."
After the USA declared war on the Central Powers in 1917, the government passed the Espionage Act. Under this act it was an offence to make speeches that undermined the war effort. Criticised as unconstitutional, the act resulted in the imprisonment of many members of the anti-war movement including 450 conscientious objectors. The Call was also prosecuted but the Appeal to Reason decided to support the war effort to remain in business.
Most members of the Socialist Party agreed with Eugene Debs but there was a small minority, including William Walling, John Spargo and Upton Sinclair, who wanted the USA to join the Allies against the Central Powers. When the pro-war section were defeated at a special conference all three resigned from the party.
During the First World War several Socialist Party members, including Kate Richards O'Hare, Victor Berger and Rose Pastor Stokes were imprisoned for their anti-war activities. After making a speech in Canton, Ohio, on 16th June, 1918, criticizing the legislation, Eugene Debs was arrested and sentenced to ten years in Atlanta Penitentiary.
People working for The Masses were also prosecuted and the magazine was forced to close. In 1918 the same people who produced the journal went on the publish The Liberator. The journal published information about socialist movements throughout the world and was the first to break the news that the Allies had invaded Russia.
After the First World War, the attorney general, A. Mitchell Palmer, became convinced that communist and socialists were planning to overthrow the American government. Palmer recruited John Edgar Hoover as his special assistant and together they used the Espionage Act (1917) and the Sedition Act (1918) to launch a campaign against radicals and left-wing organizations.
In January 1919 the Socialist Party of America had 104,000 members. The right-wing leadership of the party opposed the Russian Revolution. On 24th May 1919 the leadership expelled 20,000 members who supported the Soviet government. The process continued and by the beginning of July two-thirds of the party had been suspended or expelled.
Some of these people, including John Reed, William Z. Foster, Elizabeth Gurley Flynn, Ella Reeve Bloor, Claude McKay, Michael Gold and Robert Minor, decided to form the American Communist Party. By August 1919 it had 60,000 members whereas the Socialist Party of America had only 40,000.
The growth of the left worried Woodrow Wilson and his administration and America entered what became known as the Red Scare period. On 7th November, 1919, the second anniversary of the revolution, Alexander Mitchell Palmer, Wilson's attorney general, ordered the arrest of over 10,000 suspected communists and anarchists. These people were charged with "advocating force, violence and unlawful means to overthrow the Government".
On 7th November, 1919, the second anniversary of the Russian Revolution, over 10,000 suspected communists and anarchists were arrested in what became known as the Palmer Raids. Palmer and Hoover found no evidence of a proposed revolution but large number of these suspects were held without trial for a long time. The vast majority were eventually released but Emma Goldman, Alexander Berkman, Mollie Steimer, and 245 other people, were deported to Russia.
Eugene Debs was still in prison when he was the Socialist Party candidate in the 1920 Presidential Election. His program included proposals for improved labour conditions, housing and welfare legislation and an increase in the number of people who could vote in elections. With his running-mate, Seymour Stedman, they received 919,799 votes.
Lincoln Steffens was one of his visitors: "Debs was a happy man in prison. He loved everybody there, and everybody loved him - warden, guards, and convicts. Debs wanted to hear all about the Russian Revolution, the outrages of which he had denounced. It was not socialist, he pleaded, just as Emma Goldman declared it was not an anarchist revolution. Like so many reds who rejected Bolshevism, Debs the socialist could not abide the violence, bloodshed and tyranny."
As a result of this Red Scare people became worried about subscribing to left-wing journals and the Appeal to Reason, which was selling 760,000 a week before the First World War, was forced to close in November, 1922. The following year The Call ceased publication.
After the death of Eugene Debs in 1926 Norman Thomas became the leader of the party and was its presidential candidate in 1928, 1932 and 1936. As a result of Franklin D. Roosevelt and his successful New Deal policies, some members of the party such as David Dubinsky, called for socialists to vote for the Democratic Party, in 1936. As a result the Socialist Party vote dropped to 185,000, less than 20 per cent of that achieved in 1932. However the party continued to do well in certain cities such as Milwaukee, where Daniel Hoan was mayor of the city between 1916 and 1940.
During the McCarthy Era membership of the party fell to below 2,000 members. A large number of socialists including Walter Reuther, Philip Randolph and Bayard Rustin, left the party with the view that you had more chance of achieving progressive reform by being active in the Democratic Party.
In 1976 the Socialist Party ran a presidential campaign for the first time in twenty years. Frank Zeidler, the former mayor of Milwaukee (1948-60), was nominated as president. Other presidential candidates have included David McReynolds (1980), Sonia Johnson (1984), Willa Kenoyer (1988), John Quinn Brisben (1992), Mary Cal Hollis (1996), David McReynolds (2000), Walt Brown (2004) and Brian Moore (2008)