How Do Political Candidates
Use Poll Data?
The main difference between polls conducted for candidates and media polls is that the former are conducted for private, strategic use, while the latter are used for news analysis. Sometimes the results of private polls are leaked to the press because they serve a candidate's interests--either in support of his or her own candidacy, as a way of influencing coverage or perceptions of an opponent, or as way to influence campaign contributions. Because of their strategic use in the campaign, the results of candidate polls are usually kept confidential.
One problem with making the results of campaign polls public is that they often involve questions designed to evaluate strategic alternatives-- "what if" kinds of questions. The campaign may never carry out some (or even most) of these possible strategies, in part because of what the poll results show. Therefore, the responses to these questions are not meaningful or valid for inferring public reactions to the candidates, and they are kept private so that the campaign does not divulge its strategic intent.
Another problem with campaign polls is that they are often conducted with samples of voters that are unrepresentative of the general population. That is, a campaign may be interested in the attitudes or expected voting behavior of "independent" or "undecided" voters, or people who voted for the candidate the last time he or she ran. These results obviously cannot be generalized to the entire electorate. Sometimes such inferences are made,