Leaders, factions and the determinants of electoral success

We model the internal game between the leader and the factions of a party, to study the effect of party leadership on the determinants of electoral success. Factions are of interest or of principle. The probability of winning the election is increasing in how close the party is to the median voter, the leader's charisma, party coherence and the factions’ contributions. The leader offers both types of factions their favourite rewards in exchange for contributions. We show that party coherence and factions’ contributions are not necessarily increasing in the leader's charisma and ideological proximity to factions. Further, we show that factions of interest constraint the party's electoral strategy less than factions of principle. In particular, factions of interest always contribute more, are less of an obstacle towards achieving party coherence, and offer the party more freedom in its choice of the ideological location and charisma of the party leader.