Which Incumbents Lose in House Elections: A Response to Jacobson's "The Marginals Never Vanished"

Abstract

After the appearance of scores of scholarly works attempting to explain why incumbent members of the House of Representatives became safer in the mid-1960s, Gary Jacobson, in a recent (February 1987) article in this journal, claims that for House seats held by incumbents has not, in fact, declined. The crux of Jacobson's case rests on an alleged increase in the chances of an incumbent winning by a large margin in one election and then losing the seat two years later. Thus, Jacobson believes, marginality needs to be redefined rather than memorialized. In this response we raise some additional issues relevant to the matter of incumbent safety. Our analysis of the evidence suggests there may have been a slight, temporary increase in the late 1960s and early 1970s in the chances of big winners losing their next race, but clearly indicates that in the six elections since 1974 the proportion of big winners who lose the next election is virtually identical to the proportion in the 1950s and early 1960s. What is more, those who do lose almost always do so because of an adverse redistricting or a major, personal scandal. Thus, unlike Jacobson, we conclude that (1) there has been no meaningful increase in the chances of big winners subsequently losing and (2) in recent elections the chances of a scandal-free, unredistricted, previously safe incumbent losing are practically nil. The level of competition in congressional elections has declined and should be a source of concern to those who value electoral accountability.