The mutual majority criterion is a more broad form of the majority criterion which allows a majority to prefer multiple candidates over all of the other candidates, rather than only one; voting methods which pass the majority criterion but fail mutual majority can encourage all but one of the majority's preferred candidates to exit the election so that one of the majority-preferred candidates wins, creating a spoiler effect. The common choose-one First-past-the-post voting method is notable for this, because major political parties often attempt to prevent more than one of their candidates from running and splitting the vote, by using primary elections.