This paper uses panel data from national and state elections in India during the period 1977-2007 to examine the effect of inequality in constituency population size on voter turnout. During this period, constituency boundaries in India remained fixed. As a result, differences in population size between constituencies increased, thus changing the value of a single vote. Using this large variation in population size and informative data, this paper carefully distinguishes the effect of population size from other factors. We find that an increase of 100,000 electorates decreases voter turnout by 1.6%. In addition, we find that the share of votes gained by national political parties is greater in small-population constituencies. This suggests that political parties direct their efforts in electoral campaigns preferentially to less populous constituencies; as a result, voters in small constituencies are more likely to participate in elections.