Answer:
Polling can be misused when pollster willingly bias their polls in order to obtain a particular result that was previously desired.
Explanation:
For example, suppose a pollster wants X candidate to come on top of the poll, and knows that population Y is more likely to vote for than candidate. If the pollster then polls a higher proportion of population Y than it should according to the data of the statistical universe as a whole, then the pollster would be biasing the poll in favor of candidate X. This would be a misuse of polling.