65 ILCS 5/5-2-18.2
Electors of such city, equal in number to not less than 10% of the total vote cast for all candidates for mayor in the last preceding municipal election for such office, may petition for the submission to a vote of the electors of that city the proposition whether part of the city council shall be elected at large and part from districts. The petition shall be in the same form as prescribed in Section 5-1-6, except that said petition shall be modified as to the wording of the proposition to be voted upon, to conform to the wording of the proposition as hereinafter set forth, and shall be filed with the city clerk in accordance with the general election law. The city clerk shall certify the proposition to the proper election authorities who shall submit the proposition at an election in accordance with the general election law.
However, such proposition shall not be submitted at the general primary election for the municipality.
The proposition shall be substantially in the following form:
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Shall the city of.... elect part of the councilmen | YES |
at large and part of the councilmen from districts? | -------------------------- NO |
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If a majority of those voting on the proposition vote "yes", then at the next general municipal election and every 4 years thereafter, a mayor and part of the councilmen shall be elected at large and part of the councilmen shall be elected from wards, the total number of councilmen to be elected to equal the number of alderpersons authorized to be elected prior to adoption of the proposition.
The city council shall divide the city, whenever necessary thereafter, into districts which shall be of as compact and contiguous territory as practicable and of approximately equal population. The number of such districts shall be equal to half the number of alderpersons then authorized to be elected to office in such city. If there is an odd number of such alderpersons , the number of districts established shall be equal to the number which represents a majority of the number of such alderpersons .
One councilman, who is an actual resident of the district, shall be elected from each district. Only the electors of a district shall elect a councilman from that district. The rest of the number of councilmen authorized shall be elected at large.
The mayor and councilmen shall hold their respective offices for the term of 4 years and until their successors are elected and qualified. Upon the election and qualification of the councilmen, the terms of all sitting alderpersons shall expire.
65 ILCS 5/5-2-18.2