Whenever the electors of any city, equal in number to twenty percent of those who voted at the last regular city election, shall file a petition with the city clerk, asking that the question of organizing the city under the city manager plan of government be submitted to the electors of such city, the city clerk shall within one week certify that fact to the city council, and the city council shall, within thirty days, adopt a resolution to provide for submitting such question at a special election to be held not less than thirty days after the adoption of the resolution except as provided in this section. Any such election shall be conducted in accordance with the Election Act except as otherwise provided in the City Manager Plan of Government Act. If such petition is filed not more than one hundred eighty days nor less than seventy days prior to the regular municipal statewide primary or statewide general election, the city council shall adopt a resolution to provide for submitting such question at the next such election.