Abstract: Since the late 1980s, India’s political system has shifted from single-party dominance to an era where regional political parties (RPPs) play a critical role in both state and national governance. This paper explores the historical development, theoretical foundations, and practical ways through which regional parties influence coalition politics in India. Based on a review of existing scholarship and recent electoral outcomes, the study argues that regional parties exert influence by: (a) providing crucial parliamentary support in fragmented electoral contexts, (b) negotiating policy concessions through ministerial allocations and bargaining, and (c) shaping national agendas by bringing state-specific issues into central policymaking. The paper concludes by discussing implications for democratic representation, governance stability, and policy formulation in federal systems where regionalism and clientelism intersect with national party competition.

Keywords: Regional Political Parties, Coalition Politics, Electoral Fragmentation, Clientelism, Bargaining Power, Federalism, National Governance.