Gordon and his colleagues take this widely accepted argument a step further. Their concern lies not with the candidates’ thinking, but with the voters’. If, as previous research indicates, high-quality challengers act strategically when deciding whether to run against a Congressional incumbent, then this decision ought to convey important information to voters.

As long as voters believe that the challenger actually bears the sort of costs discussed in the literature,¹ then the challenger’s willingness to incur these costs signals to voters that the incumbent may be weak.²

Democracy is supposed to provide voters with an opportunity to hold elected officials accountable for their performance in office. With so many elected officials to monitor, however, voters would have a difficult time fulfilling this task without assistance. We have long known that challenger behavior assists voters in this judgment by determining whether voters even have a real choice to make on election day. Gordon and his colleages add to this argument by explaining that challengers also provide information to voters about the incumbent’s performance merely by deciding whether to run.

This study builds on two fields. First, it seeks to develop our understanding of retrospective voting (Fiorina 1981; Kramer 1971). Second, it contributes to the literature on the incumbency advantage and challenger quality (Cox and Katz 1996; Jacobson and Kernell 1983).

The authors present no empirical evidence to support their claims, only a formal model. Given the large body of literature already available about strategic entry, this approach is not bothersome–yet. Personally, however, I hope to see empirical evidence for these arguments in future research. The claims make good sense, but sensible, intuitive claims often lead to unexpected, counterintuitive findings when tested on real-world data.