The paper studies a simple voting system that can increase the power of minorities without sacrificing aggregate efficiency or treating voters asymmetrically. Storable votes grant each voter a stock of votes to spend as desired over a series of binary decisions and thus elicit voters' strength of preferences. The potential of the mechanism is particularly clear in the presence of systematic minorities: by accumulating votes on issues that it deems most important, the minority can win occasionally. But because the majority typically can outvote it, the minority wins only if its strength of preference is high and the majority's strength of preference is low. The result is that the minority's preferences are represented, while aggregate efficiency either falls little or in fact rises, relative to simple majority voting. The theoretical predictions of our model are confirmed by a series of experiments: the frequency of minority victories, the relative payoff of the minority versus the majority, and the aggregate payoffs all match the theory.