Three essays on campaign contributions and Congres

Chapter 1. Buying votes: A Congressman's ideological ambiguity, receipts of campaign contributions, and expected ideology. This present paper explores the relation among a Congressman's expected ideology, ideological ambiguity and the receipts of campaign contributions by using a simple one-period model in which two lobby groups compete for the Congressman's vote. First, to attract more influence-motivated campaign contributions, a Congressman should act more ambiguously when one lobby group has more advantage than the other. Second, a Congressman whose ideology is on extreme left or right will receive less in influence-motivated campaign contributions. It is interesting that a Congressman's ideological ambiguity may attract more campaign contributions although two lobby groups dislike the ambiguity by nature.;Chapter 2. How ambiguous is a Congressman? We provide a measure of a Congressman's ideology and a measure of his ideological ambiguity to be used for empirical studies. Poole and Rosenthal and Heckman and Snyder have provided excellent ways to estimate a Congressman's ideology in a multi-dimensional space via roll call voting records, but it is difficult to extend their framework to provide a measure of a Congressman's ideological ambiguity. Starting with a one-dimensional model, we use a Probit model to estimate a Congressman's ideology as well as the ideological ambiguity. We show that ideological ambiguity is one important characteristic of Congressmen's voting behavior. We also find that Congressmen who are biased to the right or to the left tend to have more ambiguous ideologies.;Chapter 3. Campaign contributions and ideology. Campaign contributions can be influence-motivated or election-motivated . In theory, influence-motivated campaign contributions should be given to unbiased (centrist) Congressmen, and a Congressman's ideological ambiguity may increase such influence-motivated contributions. On the other hand, election-motivated campaign contributions should be given to those Congressmen whose ideologies are biased to the right or to the left, and ideological ambiguity may deter such election-motivated campaign contributions. This paper conducts an empirical study of the relationship between campaign contributions and Congressmen's ideological positions, as well as the ideological ambiguity shown in roll call voting records. Our results suggest that campaign contributions tend to be given to unbiased Congressmen. That is, influence-motivated campaign contributions are more prominent. However, ideological ambiguity has no significant marginal influence on campaign contributions since Congressmen have chosen their optimal ideological ambiguities.