Mo. Const. art. VIII, § 24

1. The person receiving the greatest number of votes at a primary election as a party candidate for an office shall be the only candidate for that party for the office at the general election. The name of such candidate shall be placed on the official ballot at the general election unless removed or replaced as provided by law. 2. The person receiving the greatest number of votes at the general election shall be declared the winner. 3. Notwithstanding any provision of this section to the contrary, this section shall not apply to any nonpartisan municipal election held in a city that had an ordinance in effect as of November 5, 2024, that requires a preliminary election at which more than one candidate advances to a subsequent election. [Effective - 05 Dec 2024 , see footnote]