A friend of color admitted to me that she didn’t know much about a caucus, and was under the impression that caucusing was only for Caucasians. She was mistaken.
Merriam Webster defines a caucus as:
a closed meeting of a group of persons belonging to the same political party or faction usually to select candidates or to decide on policy; also: a group of people united to promote an agreed-upon cause
The Iowa Caucus is for all Iowans.