Adherents

• addict
• adept
• advocate
• apostle
• camp follower
• cohort
• devotee
• disciple
• follower
• henchman or henchwoman
• idealist
• ideologue
• observer
• optimist
• partisan
• party man or party woman
• pessimist
• practicer
• satellite
• sectary
• sectator
• sider
• supporter
• votary