(1) The board of commissioners of any noncharter county with a population of three hundred thousand or more, and less than four hundred thousand, may cause a ballot proposition to be submitted at a general election to the voters of the county authorizing the board of commissioners to be increased to five members.
(2) As an alternative procedure, a ballot proposition shall be submitted to the voters of a noncharter county authorizing the board of commissioners to be increased to five members, upon petition of the county voters equal to at least ten percent of the voters voting at the last county general election. At least twenty percent of the signatures on the petition shall come from each of the existing commissioner districts.
Any petition requesting that such an election be held shall be submitted to the county auditor for verification of the signatures thereon. Within no more than thirty days after the submission of the petition, the auditor shall determine if the petition contains the requisite number of valid signatures. The auditor shall certify whether or not the petition has been signed by the requisite number of county voters and forward such petition to the board of county commissioners. If the petition has been signed by the requisite number of county voters, the board of county commissioners shall submit such a proposition to the voters for their approval or rejection at the next general election held at least sixty days after the proposition has been certified by the auditor.