Photographer Stanley Tretick, best known for his iconic photos of John F. Kennedy with his children in the Oval Office, appears in the chaotic scenes as McKay reaches his victory, as part of the throng crushing around him. Tretick shot promotional stills for this and other Robert Redford films.
Groucho Marx has an uncredited walk-on cameo in what would be his last screen appearance.
A prop campaign button from this film is on display at the Smithsonian's Museum of American History in Washington. It is on display with several authentic campaign buttons.
Shot in 41 days.
The Candidate was released a month prior to the 1972 California Presidential primary. Promotional sheets were put up in southern California resembling political posters. They had simply a photo of Robert Redford, with the slogan, "McKay: The Better Way!" - "McKay" got write-in votes in the June election.
Robert Towne did an uncredited polish on Jeremy Larner's script.
Robert Redford originated the project and personally hired Michael Ritchie to direct it as he had worked as a technical adviser on various political campaigns.
Scriptwriter Jeremy Larner used to write political speeches for 1968 Presidential candidate, Eugene McCarthy.