noun (n)

• an ardent and enthusiastic supporter of some person or activity(noun.person)

  Synonym:
  partisan, partizan
  

  source: wordnet30
• a person having a strong liking for something(noun.person)

  Synonym:
  fancier
  

  source: wordnet30
• One moved or actuated by enthusiasm; as: (a) One who imagines himself divinely inspired, or possessed of some special revelation; a religious madman; a fanatic. (b) One whose mind is wholly possessed and heated by what engages it; one who is influenced by a peculiar; fervor of mind; an ardent and imaginative person.(noun)

  source: webster1913