We got three main names, William Z. Foster, Earl Browder and Norman Thomas. Ofc there are other proeminent american far left politics but openly communist I only remember those of my head. What do you think of them? How would their governments be like if they somehow grabbed power due a civil war?
Edit: Norman Thomas was a socialist, not a communist (by that be marxist Leninst or Stalininst) so he is not a option anymore.