Definition from Wiktionary, the free dictionary
kingmaker (plural kingmakers)
- Someone who has strong influence over the choice of a leader.
2012 April 23, Angelique Chrisafis, “French election: Marine Le Pen voters grapple with their role as kingmakers”, The Guardian:
- Alain, who is proud of choosing the extreme right but still didn't want his real name printed, is one of the 6.4 million Le Pen voters who are now the kingmakers in deciding who becomes the next president of France. If the Socialist François Hollande topped the poll, beating the rightwing president, Nicolas Sarkozy, and gaining momentum for returning the left to the presidency for the first time in a generation, it is Le Pen whose high showing and third place now holds the election in the balance.
- Mostly used for people with powerful influence in choosing a candidate for public representation.
person with influence in the choice of a leader
- Kingmaker, Answer.com