The election provided in Kan. Stat. Ann. § 68-517 shall be called by the board of county commissioners upon the presentation of a petition signed by at least 20 percent of the qualified electors of the county which shall be filed with the county clerk. At any such election the votes shall be taken for and against the county road unit system and if the majority of the votes cast at such election be against the county road unit system, then the county shall be restored to the original county and township road system.