Montana’s Democratic Party has written rules covering this situation and others. Below, Rule 15, for filling a vacancy in a statewide office. Download Montana Democratic Party Rules.
RULE 15 SPECIAL NOMINATING CONVENTION TO FILL A VACANCY FOR A CANDIDATE FOR A STATEWIDE OFFICE
1. In the event the Democratic Party shall have to nominate a candidate for statewide office, the procedures for such nomination shall be as provided in this rule.
2. The State Chair shall call a meeting of the Montana Democratic State Central Committee. Reasonable written notice of the meeting shall be issued unless deadlines imposed by the Secretary of State, the laws of Montana, or other authority shall necessitate shorter notice by telephone. The notice of the meeting shall include:
3. Only members of the Montana Democratic State Central Committee shall be entitled to participate in the meeting, except that the State Central Committee may adopt rules allowing nominating speeches by other persons and may agree to hear presentations by candidates for the nomination. Following the close of nominations, the members of the Montana Democratic State Central Committee shall vote. The person receiving a majority of the votes cast shall be declared the Party’s nominee. If no person receives a majority of the votes cast on the first ballot, the name of the person receiving the fewest votes shall be stricken from subsequent ballots until one person receives a majority of the votes cast.
4. The State Chair and Secretary shall sign a certificate of nomination naming the person selected and shall deliver the original to the Secretary of State.