Bradley effect
The Bradley effect, less commonly known as the Wilder effect, is a theory concerning observed discrepancies between voter opinion polls and election outcomes in some United States government elections where a white and a non-white candidate run against each other. The theory proposes that some white voters who intend to vote for the white candidate will nonetheless tell pollsters that they are undecided or likely to vote for the non-white candidate. It was named after Los Angeles Mayor Tom Bradley, an African-American who lost the 1982 California gubernatorial election to California attorney general George Deukmejian, an Armenian-American, despite Bradley's being ahead in voter polls going into the elections.
The Bradley effect posits that the inaccurate polls were skewed by the phenomenon of social desirability bias. Specifically, some voters give inaccurate polling responses for fear that, by stating their true preference, they will open themselves to criticism of racial motivation, even when neither candidate is considered "white" under the traditional rubric of American racism, as was the case in the Bradley/Deukmejian election. Members of the public may feel under pressure to provide an answer that is deemed to be more publicly acceptable, or politically correct. The reluctance to give accurate polling answers has sometimes extended to post-election exit polls as well. The race of the pollster conducting the interview may factor into voters' answers.
Some analysts have dismissed the validity of the Bradley effect. Others have argued that it may have existed in past elections but not in more recent ones, such as when the African-American Barack Obama was elected President of the United States in 2008 and 2012, both times against white opponents. Others believe that it is a persistent phenomenon. Similar effects have been posited in other contexts, for example the spiral of silence and the shy Tory factor. Bradley himself was unpopular at the state level for a variety of reasons, and went on to lose the 1986 California gubernatorial election to Deukmejian by more than 22 percentage points before settling a longstanding federal corruption probe into his alleged involvement with several multi-million-dollar illegal schemes. In 1991, Bradley would infamously describe the Justice Department's decision not to indict him, after he repaid a portion of illegally transferred funds at issue in the probe, as a "Christmas gift."