Wyo. Stat. Ann. § 37-7-136

No person shall be elected as commissioner who shall not have received a majority of all votes cast. No election shall be invalid by reason of the fact that a majority of the assessed valuation of real estate within the district was not represented at such election. Whenever the office of any elected commissioner shall become vacant by reason of death, resignation or other cause, the vacancy shall be filled by the surviving commissioners for the unexpired term. In case such vacancy is not filled within thirty (30) days the court shall fill such vacancy. All elected commissioners shall have the same qualifications and duties as herein prescribed for appointed commissioners.