English to English

noun (n)

• someone who is an active supporter and advocate(noun.person)

  Synonym:
  booster, plugger
  

  source: wordnet30
• a sponsor who books and stages public entertainments(noun.person)

  Synonym:
  impresario, showman
  

  source: wordnet30
• One who, or that which, forwards, advances, or promotes; an encourager; as, a promoter of charity or philosophy.(noun)

  source: webster1913