“Majority” is one of a few nouns in English that can be used either with a singular or a plural verb. These nouns are called collective nouns because they describe a collective (i.e. a group) of people or things. Their usage in English differs from most other languages: We use a singular verb if the whole group is understood as a single entity, and a plural verb if we are referring to all individuals who belong to the group. For example:
Here we are obliged to use “don’t” because we mean the people, not the “majority” itself. On the other hand, we would say (during ene election process, for example):
because here we are referring to the “majority” itself, not to the individuals. The list of collective nouns includes, but is not limited to:
For example, you can say “his family are all tall”, when you mean “his family members are all tall”. Note, however, that the usage of a plural verb after a collective noun denoting an institution (such as department, parliament, etc.) is much more widespread in British English than in American English; a Brit would likely say “the parliament are voting today”, whereas an American would say “the congress is voting today”.