Mo. Rev. Stat. § 115.313: Petitions to form new party or nominate independent candidates, who may sign.

Any person who is a registered voter of the state of Missouri may sign a petition for the formation of a new political party or for the nomination of an independent candidate for office. Any person who signs a name other than his own to any petition or knowingly signs his name more than once to the same petition or who knows he is not a registered voter at the time of signing such petition, or any officer or person willfully violating any provision of this subchapter, shall be guilty of a class two election offense.