ST. LOUIS (AP) — Now that Missouri’s minimum wage is back to $7.70 statewide, the Democratic mayors from both of the state’s big cities are supporting a ballot measure to increase the wage to $12 an hour gradually by 2023.

St. Louis Mayor Lyda Krewson was among several dozen supporters of a higher minimum wage who gathered Monday for a rally and protest. Krewson says she’ll be asking for signatures on a petition toward a November 2018 ballot measure. The effort called “Raise Up Missouri” requires 100,000 signatures by May.

Kansas City Mayor Sly James says in a statement that he also supports the ballot initiative. Other supporters include Columbia Mayor Brian Treece and St. Louis County Executive Steve Stenger.

A Missouri law that went into effect Monday prohibits local government from approving minimum wages higher than the state’s. The measure overturns a $10 wage in St. Louis that went into effect in May, and nullifies voter approval of a $10 wage in Kansas City.