Possible Clues:

• Revolutionary to spoil mark on ballot paper
• Writer on class struggle
• Karl, Richard or Harpo
• Surname of four "Animal Crackers" actors
• Run into Weber or another economist
• Harpo, Zeppo or Groucho
• Comedian's impressions on podcast
• Groucho —, comic
• Who said history repeats itself 'the first time as tragedy, the second time as farce'
• Harpo, Groucho, or Chico