Responsiveness of politicians is one of the basic assumptions of party mandate theory, which is in pledge approach translated into expectation of inherent willingness of parties to fulfill (as many as possible) definitive promises given to voters in manifestos while facing obstacles limiting their attempts. Scholars rooted in the pledge approach have found a big amount of factors influencing the ability of parties to fulfill their promises, and, regardless to the varying percentage of fulfillled promises, assumption of the willingness of parties to fulfill the pledges has not been challenged. In the pledge approach, just definitive pledges are extracted from manifestos and furhter analysed. However, in everyday politics, candidates for public offices regularly make vague (non-definitive) statements that leave voters uncertain about the policies they intend to pursue. In this paper, the formulation of unspecific pledges is seen as the rational strategy of at least some kinds of parties. The concept of strategic ambiguity is applied to the study of party competiton in multiparty systems, and for study of pledges in electoral manifestos. In the paper, I introduce the concept of strategic ambiguity, which has mostly been studied in the US context, and its application to the multiparty competition, where the concept is connected to the saliency of policy topics for different parties. I deduce hypotheses concering party stratgies regarding the ambiguity of pledges in party manifestos. I hypothesize that parties formulate more definitive pledges in their salient policy topics and in topics, which are generally salient for all parties. Otherwise, I expect that parties formulate vaguer pledges in their secondary political topics. I also hypothesize that government parties (as high-quality candidates) have bigger overall odds to formulate vague pledges, on the other hand, parties newly entering the electoral arena (as low-quality candidates) have bigger odds to formulate definitive pledges at all, because they feel that they have nothing to lose. In the empirical part, the hypotheses are tested at manifestos of Czech parliamentary parties (2006-2013) – pledges (definitive and vague) are extracted from manifestos and the hypotheses are tested with binary logistic regression (vagueness of pledge in manifesto as dependent variable).
