The phrase "king makers" refers to influential people or a group who have the power to influence and decide who becomes the ruler or leader of a country or organization. Full definition
While he's unlikely to play king maker publicly, he could still influence the national race behind the scenes. (macleans.ca)
He lost seats but still he became king maker. (nextleft.org)
Three this occurs before the budget passes and the elections happen after the budget passes, meaning the IDC just gets themselves locked out of the budget process and Felder becomes king maker in the budget process. (nystateofpolitics.com)