One experience I had (coming from an Austrian right wing province) is that a significant share of polled people will not reveal to the pollster they are voting for the xenophobic candidate, because they don't want to be seen as a bigot.
It is like when your doctor is asking you if you eat fast food — some people will downplay it because they know it is wrong, but do it anyways in a "weak" moment when nobody is looking.
So suddenly in my village where I know everybody 56% voted for the right wing candidate, yet everybody¹ claimed not to do that when asked before or after.
Polling isn't merely a reporting of raw responses, but a calibrating of those responses to known bias factors. Those might be psychological (as you describe) where people are reluctant to reveal actual preferences, but also include numerous others:
- Who does or does not have a phone.
- Who will or won't answer a phone.
- Specific target demographics, under the rubric of "stratified random sampling".
Just a few off the top of my head.
As I'd mentioned upstream, political polling has regular calibration events called "elections", and following those events biases and adjustment factors, most falling out of statistical analysis and correlations, rather than "gut feels", are updated.
The problem for the US seems to be that the biases are accelerating well in advance of those adjustments, as my own poll-vs-vote analysis shows:
It is like when your doctor is asking you if you eat fast food — some people will downplay it because they know it is wrong, but do it anyways in a "weak" moment when nobody is looking.
So suddenly in my village where I know everybody 56% voted for the right wing candidate, yet everybody¹ claimed not to do that when asked before or after.
¹: except one or two open Nazis