Precinct caucus is held tonight March 6 at 7:00 p.m. MT for the two major parties. In order to vote registration for example Republican was needed by early January. If you are a long-time party member attend and meet your neighbors and vote for precinct leaders, vote for representatives and alternates to county, state, and various district assemblies. There are fees to attend the assemblies that cover rental costs, insurance, and other costs for the events.
Find info for caucus locations:
Arrive early for registration.
Expect to see at least some of the candidates at the caucus.
Note: Vacancies for say your local state house district would be filled by a call to precinct leaders to assemble for review of candidates and a vote.