Possible Clues:

• Vocal team supporter
• Pep rally participant
• Vocal supporter
• Console captain who makes a song and dance at ball game?
• Girl crying out for a successful match?
• During the game, she's no reserve!
• Head of an organised supporters' group
• Shouter of this puzzle's circled sounds
• Rouser of crowd, a revolutionary, puts bullets into two monarchs
• Organiser of support for a sports team