There is no viable U.S. Socialist Party today as there was in the early 1900s. The late-twentieth-century Socialist Party--the one that comes out of the Eugene Debs and Norman Thomas tradition--is so small as to be almost negligible on the U.S. political scene. Other leftist parties in the United States--many in the Marxist-Leninist or Maoist tradition--are even more fragmented and isolated from mainstream U.S. politics. Two somewhat more viable progressive--leftist electoral formations today--the Democratic Socialists of America (which is an offshoot of the U.S. Socialist Party and was created through the merger of the Democratic-Socialist Organizing Committee and the New American Movement in 1982) and the Rainbow Coalition (the electoral base for Jesse Jackson 1984 and 1988 Democratic presidential campaigns, which has organizations in a number of states, including Vermont)--both are still pre-party formations and are very small in comparison to the early-twentieth-century Socialist Party.
If there were still a viable Socialist Party today, Bernard Sanders probably would belong to it. Given how strongly Sanders identified with Debs, it is ironic that he falls within the moderate/right-wing tendency (that is, the Hillquit and Berger tradition) of the old Socialist Party rather than the syndicalist/left-wing tendency (that is, the DebsHayward tradition). Sanders definitely sees elections as a viable and important means for moving toward socialism, while Debs and others saw elections more as an educational vehicle of the masses. Sanders puts a lot more faith in electoral politics and its potential accomplishments than Debs ever did. Thus, if there were a viable Socialist Party today with the same tendencies that existed in the early twentieth century, Sanders probably would receive a lot of criticism for practic-