A campaigner who is wearied can also be described as a disillusioned activist, a fatigued advocate, or a jaded crusader. These synonyms capture the sense of exhaustion and disillusionment that comes from fighting a long, difficult, and seemingly endless battle. Other possible synonyms for wearied campaigner might include world-weary spokesperson, battered protester, and battle-worn lobbyist. These terms all suggest someone who has been through the trenches and come out on the other side, but who is now feeling the weight of their experience and struggling to maintain their passion and energy. Ultimately, a wearied campaigner is someone who deserves our respect and admiration for their commitment to a cause, despite the challenges and obstacles they face.