What is another word for "ally"?

Roget's Thesaurus (1911) lists these synonyms for "ally": abettor, accessory, accomplice, acquaintance, adherent, adjunct, adjutant, adjuvant, advocate, after, all, alter, ambo, amigo, and, angel, assistant, associate, auxiliary, backer, bedfellow, best, boon, bosom, candle, casual, chamber, champion, childhood, chum, classman, classmate, clerk, coadjutor, coadjutrix, collaborator, colleague, companion, compatriot, compeer.