Does electoral fraud stabilize authoritarian rule or undermine it? The answer to this question rests in part on how voters evaluate regime candidates who engage in fraud. Using a survey experiment conducted after the 2016 elections in Russia, the authors find that voters withdraw their support from ruling party candidates who commit electoral fraud. This effect is especially large among strong supporters of the regime. Core regime supporters are more likely to have ex ante beliefs that elections are free and fair. Revealing that fraud has occurred significantly reduces their propensity to support the regime. The authors’ findings illustrate that fraud is costly for autocrats not just because it may ignite protest, but also because it can undermine the regime’s core base of electoral support. Because many of its strongest supporters expect free and fair elections, the regime has strong incentives to conceal or otherwise limit its use of electoral fraud.