Bradley effect is the term given to a bias commonly found in controversial polling results: respondents overstate their support for the “politically correct” answer. The “Bradley” refers to former Los Angeles mayor Tom Bradley, an African American whose polling results indicated much greater support than he got in the closely contested 1982 California governor’s race. In 2016, the politically correct answer on the Republican side is “not Trump.” Is Trump’s support understated in the polls?
To be fair, there is little clear evidence that Trump is affected by the Bradley Effect, or, in his case, a Reverse Bradley Effect so far in the primaries: his support does not appear to have been understated in the polls compared to his actual votes against other Republicans. What makes me wonder is, for all the talk about how many establishment Republicans hate Trump, how many of them will actually desert him to vote for Hillary Clinton? Is there a good way to estimate this?