Bill Sponsorship in Congress: The Moderating Effect of Agenda Positions on Legislative Proposals

Positions of influence over the legislative agenda provide greater opportunities for shaping policy outcomes. Do legislators take advantage of this? If they do, when the median is pivotal and legislators' goals reflect both position taking and policy seeking, greater influence over the agenda leads legislators to moderate their bills relative to legislators with lower agenda priority. Analysis of a formal game theoretic model provides rigorous justification for the proposition, and empirical analysis of House and Senate bills from the 101st to 108th Congresses using cosponsorship data to measure the ideological locations of bills largely supports it. Committee leadership and majority party status have moderating effects while the effect of committee membership is slight. The analysis also tentatively supports the pivotalness of the median over other alternatives. Contrary to the view that bill sponsorship is mere position taking, legislative organization significantly shapes early-stage legislative behavior. Specifically, greater legislative influence implies greater responsiveness to the median legislator.