C.R.S. § 31-2-302

Upon the petition of the registered electors of any such town or city equal in number to ten percent of the votes cast for all candidates for mayor at the last preceding regular election, the governing body thereof shall immediately, by ordinance or resolution, call a special election on the question of organizing under this title. Such question shall be submitted to the registered electors of the city or town at a special election to be held on the date set by the governing body and conducted in accordance with the provisions of the “Colorado Municipal Election Code of 1965”, insofar as possible.