advocator vs protagonist

Other hyponyms of advocator include apologist, justifier, vindicator, commie, communist, constitutionalist, Darwinian, democrat, populist, fascist, federalist, Gnostic, humanist, humanitarian, ideologist, ideologue, internationalist, irredentist, irridentist, isolationist, Jansenist, libertarian, Maoist, Marxist, nationalist, neoclassicist, neutralist, nullifier, drumbeater, partisan, zealot, partitionist, Platonist, pro-lifer, presenter, sponsor, protectionist, republican, ritualist, ruralist, secessionist, secularist, separationist, separatist, interpreter, representative, spokesperson, voice, suffragist, admirer, booster, champion, friend, supporter, supremacist, teleologist, Thatcherite, unilateralist, voice in the wilderness.