It is well known that different types of electoral systems create different incentives to cultivate a personal vote and that there may be variation in intra-party competition within an electoral system. This article demonstrates that flexible list systems – where voters can choose to cast a vote for the list as ordered by the party or express preference votes for candidates – create another type of variation in personal vote-seeking incentives within the system. This variation arises because the flexibility of party-in-a-district lists results from voters' actual inclination to use preference votes and the formal weight of preference votes in changing the original list order. Hypotheses are tested which are linked to this logic for the case...