white knight

a person who actively supports or favors a cause a deserving cause in need of a charismatic white knight who will galvanize public support Synonyms advocate, advocator, apostle, backer, booster, champion, expounder, espouser, friend, gospeler (or gospeller), herald, hierophant, high priest, paladin, promoter, proponent, protagonist, supporter, true believer, tub-thumper, exponentRelated Words loyalist, partisan (also partizan), stalwart; adherent, cohort, disciple, follower; interpreter; applauder, cheerleader, encourager, fellow travelerNear Antonyms enemy, foe, rival; belittler, critic, faultfinderAntonyms adversary, antagonist, opponent