Any municipality having a population of three thousand or more persons according to the last federal census or any other official census may be organized and governed as a commission-manager municipality if the qualified electors of the municipality elect to be governed under the commission-manager form of government. If the qualified electors of the municipality do not elect to be governed under the commission-manager form of government, the municipality shall be governed under the form of government in existence on the day the election rejecting the commission-manager form was held.