We present a model of participation in large elections in which the formation of voter groups is endogenous. Partisan citizens decide whether to become leaders (activists) and try to persuade impressionable citizens to vote for the leaders' preferred party. In the (unique) pure strategy...

We model electoral competition between two parties in a winner-take-all election. Parties choose strategically first their platforms and then their campaign spending under aggregate uncertainty about voters' preferences. We use the model to examine why campaign spending in the United States has...