In the United States, competitive elections are often concentrated in particular places. These places attract disproportionate attention from news media and election campaigns. Yet many voting studies only test stimuli in uncompetitive environments, or only test for average effects, and simply assume the results are relevant to competitive contexts. This article questions that assumption by utilizing Election Day inclement weather as an exogenous and random cost imposed on voters. We test how voters in competitive and uncompetitive environments respond to this random cost and find that while rain decreases turnout on average, it does not do so in competitive elections. If voters in different electoral contexts do not react the same way even to rain, then serious doubt should meet claims that voters will react the same way to campaign appeals, economic factors, or other treatments tested in the literature. Careful consideration of effects that are heterogeneous with respect to electoral context can make the difference between a result that calls democracy into question and one that is politically irrelevant.