Size, density and small scale elections: A multi-level analysis of voter turnout in sub-municipal governments

What are the consequences of fragmenting political and administrative authority within municipalities? Portugal provides an excellent setting to study the effects of sub-city institutional fragmentation because each of its 308 municipal governments is divided into sub-municipal governments (SMUs). The 4259 SMUs deliver services to the residents and its executive leader serves on the city council. In this paper we investigate the determinants of voter turnout in these SMUs. We argue that the size and density of SMUs affects electoral participation, but this effect is mediated by the municipal context. High levels of population concentration and low levels of territorial fragmentation at the municipal level are expected to improve voter mobilization efforts and mitigate the negative effect of size and density on voter turnout. Hierarchical linear analysis of municipal and SMU data finds strong support for size and density effects and moderate support for multilevel relationships.