With growing awareness of the importance of establishing good relationships with immediate stakeholder groups the scope of sponsorship broadens. Management objectives concerning sponsorship are now often either commercial or relational in nature. As most studies focus on the assessment of the economic effectiveness of sponsorship activities this research investigates how sponsorship can aid in the achievement of a relational objective, specifically the development of citizen commitment towards a public authority. Questionnaire data from 237 spectators of a publicly sponsored sports event were collected and analysed. The findings suggest a rational model of sponsorship effectiveness and support congruence theoretical considerations. The strongest determinants of commitment towards the sponsor are positive attitudes towards the sponsorship activity, the belief that public sponsorship is seen as beneficial for the region. Further, positive attitudes towards the sponsorship depend on whether citizens perceive the sponsorship activity to be a waste of financial resources. This corroborates the idea that sponsorship activities with relational objectives are elaborated on the normative belief whether tax money should be used to sponsor an event. Public sector bodies should also pay attention to explicitly communicate the reasons and benefits of the sponsorship activity in order to enhance perceived event-sponsor congruence. This study explains the dynamics in the sponsorship model that impact on the achievement of relational objectives and identifies managerial implications on how to manage sponsorship activities in a public sector context.