Does democratization imply faster growth, less corruption and less inefficiency? Past studies yield ambiguous results on the effects of democracy on economic performance and growth. We develop a simple two-sector endogenous growth model that shows both very young and mature democracies grow faster than countries in mid stages of democratization, producing a 'U' effect. This effect results from the pattern of rent seeking as it diverts from the provision of public goods. Rent-seekers act as monopolistic competitors. Initially, more democracy increases their number, raising aggregate rents. However, rents per rent-seeker fall with the number of rent seekers, aggregate rents fall in mature democracies. Thus, rents show an 'inverted-U' effects in relation to democracy. We find fairly robust supportive evidence for the latter.