Do Newspapers' Candidate Endorsements Work?

Yes, say Brian Knight and Chun-Fang Chiang of Brown in a new NBER working paper (free version). But it depends on the newspaper (and probably the assumptions Knight and Chiang make in their model):

This paper investigates the relationship between media bias and the influence of the media on voting in the context of newspaper endorsements. We first develop a simple econometric model in which voters choose candidates under uncertainty and rely on endorsements from better informed sources. Newspapers are potentially biased in favor of one of the candidates and voters thus rationally account for the credibility of any endorsements. Our primary empirical finding is that endorsements are influential in the sense that voters are more likely to support the recommended candidate after publication of the endorsement. The degree of this influence, however, depends upon the credibility of the endorsement. In this way, endorsements for the Democratic candidate from left-leaning newspapers are less influential than are endorsements from neutral or right-leaning newspapers, and likewise for endorsements for the Republican. These findings suggest that voters do rely on the media for information during campaigns but that the extent of this reliance depends upon the degree and direction of any bias.

According to their model, a paper like the Washington or Denver Post has more influence than papers like NYT or the Dallas Morning News. The reason: NYT and the Dallas Morning News are much more likely to pick a Democrat and a Republican, respectively, than either of the Posts. And since readers take into account the perceived slant of a paper's editorial board, publications like the two Posts will have more of an impact since they can surprise readers more.

For the record, Obama is leading McCain 194 to 82 in endorsements, a two-to-one edge, says Editor & Publisher. Obama endorsing papers have a total of 20 million in circulation while McCain backing papers only sell 6 million issues per day.