Kingmaker

Origin

From king + maker.

Full definition of kingmaker

Noun

1. 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, 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.

Usage notes

Mostly used for people with powerful influence in choosing a candidate for public representation.