Fellow traveller
"Fellow traveller" is a term, often pejorative, for a person who sympathizes with the beliefs of an organization or cooperates in its activities without maintaining formal membership in that particular group. The term was used in the early Soviet Union to characterize writers and artists sympathetic to the goals of the Russian Revolution who declined to join the Communist Party. The English-language phrase came into vogue in the United States during the 1940s and 1950s as a pejorative term for a sympathizer of Communism who was nonetheless not an official or "card-carrying member" of a Communist party. 'Fellow travellers' were often accused of lending their names and prestige to Communist front organizations. In other languages the comparable terms are compagnon de route, sympathisant or progressistes in French; Weggenosse or (more generally) Sympathisant in German; and compagno di viaggio in Italian.