champion

nouns

someone who has won first place in a competition

champ, champion, title-holder

someone who fights for a cause

champion, fighter, hero, paladin

a person who backs a politician or a team etc.

"all their supporters came out for the game"; "they are friends of the library"

admirer, booster, champion, friend, protagonist, supporter

someone who is dazzlingly skilled in any field

ace, adept, champion, genius, hotshot, maven, mavin, sensation, star, superstar, virtuoso, whiz, whizz, wiz, wizard

protect or fight for as a champion

champion, defend

holding first place in a contest

"a champion show dog"; "a prizewinning wine"

champion, prizewinning