AMERICAN POLITICS QUARTERLY / OCTOBER 1999King / RUNNING ON THE R OWN RUNNING ON THEIR OWN The Electoral Success (and Failure) of Appointed U.S. Senators

Senators who first reach office by gubernatorial appointment are successful at the polls at half the rate of incumbents in general. Outcomes of elections featuring appointed senators are affected by the incumbent’s voting record in the Senate, the divisiveness of the primary, state par-tisanship, the size of the state, national political conditions, and the quality of the challenger. This last factor is the key to understanding the anomaly, as appointed senators face higher quality challengers than do senators who first gain office through the electoral process. Incumbency is a major force in American elections. Governors and U.S. senators are usually successful in their reelection bids; electoral defeats are even rarer for members of the U.S. House of Representa-tives. There is a class of incumbents, however, that does not enjoy a high rate of success at the polls. Senators who first reach office by gubernatorial appointment are successful at the polls at half the rate of incumbents in general. Between 1948 and 1996, 78.7 % of all incum-bent senators seeking reelection were returned to office by the voters (Stanley & Niemi, 1998). During that same period, only 38.3 % of appointed senators were successful in their first election after gaining office. This pattern has been noted before (Clem, 1966; Matthews, 1960; Morris & Marz, 1981), but the reasons for the disparity are unclear. A host of factors known to influence Senate election out-comes have not been explored in the context of the election of appointed senators. This article applies the lessons of previous Author’s Note: My thanks are extended to Helenan S. Robin, Carole Kennedy, the editor and reviewers of American Politics Quarterly for their comments at various stages of this project, and Jim Hellyer for his assistance in data collection. None of these individuals bears any responsibil