What underlying logic explains candidate participation in vote buying, given that clientelist exchange is so difficult to enforce? We address this question through close analysis of campaigns by several dozen candidates in two electoral districts in Java, Indonesia. Analyzing candidates' targeting and pricing strategies, we show that candidates used personal brokerage structures that drew on social networks to identify voters and deliver payments to them. But these candidates achieved vote totals averaging about one quarter of the number of payments they distributed. Many candidates claimed to be targeting loyalists, suggestive of "turnout buying," but judged loyalty in personal rather than partisan terms, and extended their vote-buying reach through personal connections mediated by brokers. Candidates were market sensitive, paying prices per vote determined not only by personal resources, but also by constituency size and prices offered by competitors. Accordingly, we argue that a market logic structures Indonesia's system of vote buying.