Mo. Rev. Stat. § 72.180: Consolidation effective, when — more than two cities, vote against, effect.

If it shall appear that a majority of the votes cast in each one of said municipalities on the question shall be in favor of consolidation, the certificate of the clerk shall be recorded in the journal of the council, board of trustees or board of aldermen of each of said cities, towns or villages, and consolidation of such cities, towns or villages thereafter be consummated. Where more than two cities, towns or villages as provided in section 72.150, seek consolidation, a majority of the votes cast in any one city, town or village against the consolidation shall not prevent the consolidation of the remaining cities, towns or villages if a majority of the votes cast in such remaining cities, towns or villages are in favor of consolidation unless a majority of the votes in the largest of the cities, towns or villages seeking consolidation is against consolidation, in which case the consolidation shall be deemed to have been defeated.