campaigner
n. B2 Upper Intermediate US //kæmˈpeɪnɝ// UK //kæmpˈeɪnɐ// cam·paign·er
n. a person who works hard to support a cause or a political candidate. You use this for someone who is very active in trying to change a situation.
n. a person who actively supports a cause, candidate, or policy. Often used to describe individuals who engage in public advocacy or political mobilisation.
She is a dedicated campaigner for animal rights.
The local campaigner spent months organizing the community to vote for the new park.
Despite facing significant opposition from the establishment, the grassroots campaigner managed to secure enough signatures to force a public referendum on the proposed law.