caucus
ˈkɔːkəs
noun
(in some US states) a meeting at which local members of a political party register their preference among candidates running for office or select delegates to attend a convention.
Hawaii holds its nominating caucuses next Tuesday
meeting,assembly,gathering,congress,conference,convention,rally,conclave,congregation,convocation,synod,council,session,parley,get-together
verb
hold or form a legislative caucus.
Republicans briefly caucused