Minor party and independent presidential candidates are generally kept out of debates with their major party opponents. Generally, minor party and independent presidential candidates do get a chance to debate each other, but many such candidates seem afraid to “debate down”, i.e., debate with some of their opponents who have smaller campaigns.
“Debating down” paid off handsomely for Norman Thomas in 1948, however. The 1948 Republican presidential primary process had a radio debate between Thomas Dewey and Harold Stassen, on May 17, 1948, just before the Oregon Republican presidential primary. That was the first presidential candidates’ debate in U.S. history. It stimulated calls for a general election debate. Henry Wallace, a former vice-president of the U.S., and the Progressive Party nominee in 1948, challenged Harry Truman and Thomas Dewey to a general election debate. Truman and Dewey refused. Then Norman Thomas, Socialist Party presidential candidate in 1948, challenged Wallace to a debate. Wallace refused. Then Edward Teichert, the Socialist Labor Party presidential candidate, challenged Thomas to a debate. Thomas accepted, but said that the Socialist Workers Party presidential candidate, Farrell Dobbs, should also be invited. Teichert then refused, so Thomas and Dobbs had the nation’s first-ever general election presidential debate.
Thomas helped himself considerably by participating. The debate was in New York city, and attracted media attention in New York. At the November 1944 election, Thomas had only polled 10,553 votes in New York state, whereas the 1944 showing for the Socialist Labor presidential candidate in New York had been 14,352. But at the 1948 election within New York state, the results were: Thomas 40,879; Teichert (the Socialist Labor candidate) 2,729; Dobbs (the Socialist Workers candidate) 2,675. Thomas gained enormous respect for being principled enough to debate other presidential candidates who had smaller campaigns.