Political Party Unity

The argument that the invisible primary is the critical period of the nomination campaign is contingent on the unity of the party coalition. The extent to which parties will coalesce around a candidate during the invisible primary depends in part on the relative unity of the party coalition. ¹ While the coalitions that form the parties are durable, some degree of coalition change occurs in every presidential nomination. ² Both long- and short-term factors affect party unity in presidential nomination campaigns.