Bradley-Wilder a thing of the past?

[RichardRay]

The 'Bradley-Wilder Effect' (of just the 'Wilder Effect') is the discrepancy between stated support for black candidates and actual voting results. There is substantial evidence to support the existence of something like a 2.7% overstatement of voter support in polls based on respondents unwillingness to honestly tell pollsters that they are unwilling to vote for a black candidate. The effect was first noted in Tom Bradley's suprising loss in the California gubernatorial race in 1982, and substantiated in the narrow wins in the gubernatorial race of Douglas Wilder in Virginia in 1989, David Dinkins mayoral candidacy in NYC in the same year. Concern has been raised in this election cycle that Barack Obama's lead in the polls needs to be discounted by as much as 3% to allow for this factor.

A recent paper supports the existence of the Bradley-Wilder effect in the past, but finds no evidence to support its continuing impact. It also fails to find any evidence of what has been termed the 'Whitman Effect'; a similar impact on female candidates.

No More Wilder Effect, Never a Whitman Effect:
When and Why Polls Mislead about Black and Female Candidates

Abstract

The 2008 election has renewed interest in the Wilder Effect, the gap between the share of survey respondents expressing support for a candidate and the candidate's vote share. Using new data from 133 gubernatorial and Senate elections from 1989 to 2006, this paper presents the first large-sample test of the Wilder Effect. It demonstrates a significant Wilder Effect only through the early 1990s, when Wilder himself was Governor of Virginia. Although the same mechanisms could impact female candidates, this paper finds no such effect at any point in time. It also shows how polls' over-estimation of front-runners' support can exaggerate estimates of the Wilder effect. Together, these results accord with theories emphasizing how short-term changes in the political context influence the role of race in statewide elections. The Wilder effect is the product of racial attitudes in specific political contexts, not a more general response to under-represented groups.

Daniel J. Hopkins
Post-Doctoral Fellow
Department of Government
Harvard University
dhopkins -at- iq -dot- harvard -dot- edu
July 21, 2008

Full Text (pdf)