U.S. Senate Elections before the 17th Amendment: Political Party Cohesion and Conflict 1871–1913

From 1789 to 1913, U.S. senators were indirectly elected by state legislatures; this electoral mechanism ostensibly girded U.S. senators against the instability of public opinion and insulated them from direct public pressures. The adoption of the 17th Amendment in 1913 replaced this system with the direct election of senators. In this article, we use an original data set of recorded ballots for U.S. Senate elections in state legislatures from 1871 to 1913 to illustrate the dynamics of indirect elections. Our broad goal is to identify components of the process that shed light on who was elected to the Senate under this type of electoral system and how indirect elections fared as a mechanism of representation. We find significant evidence that under the indirect electoral mechanism, Senate elections were contentious, and winning majority control of the state legislature did not always ensure an easy electoral process. Specifically, the breakdown of caucus nominating processes, the size of majority coalitions, and whether the incumbent senator was running for reelection each exerted an effect on the probability of conflict in the indirect election process.