Montana Title 13. Elections § 13-25-205. Nominations for special election

(1) When a special election is ordered to fill a vacancy in the office of United States senator or United States representative, each political party shall choose a candidate according to the rules of the party. Nominations by parties must be made no later than 75 days before the date set for the election.

(2) Nominating petitions may be filed by independent candidates for the office up to 5 p.m. of the 75th day before the election.