Why regional parties succeed at the sub-national level in India

Existing scholarship in comparative politics has either focused on regionalism or on political and economic decentralisation to explain the growth of regional parties. Using quantitative evidence from India, I show that a hitherto ignored explanation, the level of regional branch autonomy within polity-wide parties, also has a significant impact on the growth of regional parties. When regional branches of polity-wide parties have autonomy, regional parties find it difficult to grow. In contrast, regional parties benefit electorally when regional branches of polity-wide parties are less autonomous. To further account for endogeneity between regional party growth and regional branch autonomy, I use quantitative and qualitative evidence to show that the growth of regional parties is not positively correlated with more regional branch autonomy.