What bradley effect occurs when?
1 say they will vote for a candidate but then vote against him or her (because of race) 2 is just wrong. https://en.wikipedia.org/wiki/Bradley_effect
The Bradley effect theorizes that in person-to-person polling, many people will give the socially acceptable response to the polling question even if they do not share that view. Since opposing a minority or female candidate based on race and gender or supporting a racist candidate is socially unacceptable, the poll shows good results for the minority candidate and bad results for the racist candidates. When the voter gets in the voting booth, however, since the ballot is secret, they vote their true beliefs resulting in a swing away from minority candidates and towards racist candidate. For obvious reasons, this result is less significant and almost non-existent for robopolls (which are becoming more common).
The Bradley Effect is when voters want pollsters to believe they're "enlightened" and would vote for a minority/female only for them to then not vote for that person in the election. It skews the polls and is likely part of what caused the polling on the Clinton campaign to be so wrong.