This article introduces centrality in covoting networks as a measure of influence. Based on a simple cueing dynamic, it conceptualizes those lawmakers as most centraland thus as having the greatest signaling influence-who impact the greatest number of colleagues' voting decisions. A formal proof and an agent-based simulation show that cue-providers are always more central than followers; hence, we can use real-world voting data to identify the most influential legislators. To confirm the measure's construct validity, we predict covoting centrality in the European Parliament and find those factors that are expected to impact legislators' influence to predict their centrality.Political actors are not created equal. Some are more influential than others, be it due to the formal positions of power they hold, positive personal traits like skills, experience, expertise, ambition, and determination, or less positive traits, like a lack of scruples. Yet, measuring political power and influence is exceedingly difficult. In this article, we introduce a new measure of influence that draws from the study of power in social networks: political actors' centrality in covoting networks. Specifically, we use legislators' voting patterns to measure their social connectedness and, on this basis, examine the structural positions of individual lawmakers to determine their relative influence (Bailey and Sinclair 2008). The basis for this conceptualization of voting as a relational activity is a simple cueing dynamic in which some lawmakers (cue-receivers) follow the lead of select colleagues (cue-providers) when voting in a legislature. Those legislators whose cues influence the greatest number of colleagues' voting decisions are most central in the legislative covoting network and thus have the greatest signaling influence. 1 We maintain that cue-providers should always be more central than their followers in covoting networks, which allows us to identify those legislators who are most influential in the sense that their signals affect the votes of the greatest number of colleagues. We make this case, LEGISLATIVE STUDIES QUARTERLY, 41, 2,