In the film, it is suggested that Joan Blondell's character got the idea of the numbers racket from her assistant, "Nellie". In reality, the numbers racket was pioneered by black gambling racketeers in Harlem. The "Nellie" character was based on Stephanie "Madame Queen" St. Clair (Nellie scoffs at being called "Madam Nellie"). As in the film, the numbers racket was eventually taken over by "Dutch" Schultz and "Lucky" Luciano (The Humphrey Bogart and Barton MacLane characters, respectively).
This film was made as part of Warner Bros.' response to the Production Code Administration and the Legion of Decency, which had condemned the studio's previous gangster movies with Edward G. Robinson and James Cagney as glorifying the criminal life. In response, Warners had both actors make crime movies with their characters on the right side of the law, with Cagney playing an FBI agent in "G-Men" and Robinson playing an undercover cop here.
"Bullets or Ballots" was so successful at the box office that it gave Edward G. Robinson the clout to negotiate a new contract with Warner Bros., which gave him rights of story and script approval and allowed him to make one movie per year for another studio.