There are a number of studies on the methodology of polling that suggest the margin of error is much wider than typically reported by polls by about an order of magnitude in part due to sample size. Although there are a number of non-sample size related issues, like the one you mentioned and people misreporting/lying, at play as well.
There are a number of studies on the methodology of polling that suggest the margin of error is much wider than typically reported by polls by about an order of magnitude in part due to sample size. Although there are a number of non-sample size related issues, like the one you mentioned and people misreporting/lying, at play as well.