Mo. Rev. Stat. § 92.329

The governing body of any city may, by adopting an ordinance, impose the convention and tourism tax, but no ordinance enacted pursuant to the authority granted by the provisions of sections 92.325 to 92.340 shall be effective unless the governing body of the city submits to the voters of the city at a citywide general or primary election or at a special election called for that purpose, a proposal to authorize the governing body of the city to impose the convention and tourism tax.