In The Symbolic Uses of Politics, Murray Edelman had this to say about public opinion polling:
A related kind of ambiguity pervades political process as well: uncertainty about how much public support or opposition for programs exists or can be created. Because opinion is constructed and volatile, all indicators of it are problematic. Poll reports are therefore another device for the reduction of ambiguity to clarity.
Polled individuals are abstracted both from their everyday lives and from political discussion and action shared with others. Their opinions are therefore also abstract — not necessarily related to any course they would pursue when involved in political activities different from answering an interviewer (or, perhaps, voting). In this artificial situation expressed opinion depends upon verbal cues together with changing memories of past situations and anticipations of future ones. Polls and surveys generate numbers that have the dramaturgical look of hard data and the epistemological look of shifting fantasies.
In his essay “Public Opinion Does Not Exist,” Pierre Bourdieu similarly deflates polling as an elaborate trick that elites use to claim to speak for ‘the people.’ This mechanism, which measures aggregated answers of individuals, who are extracted from any organic social context, to questions about matters that they may or may not have any prior concern or idea about, has an inherently conservative bias to it. This conservative bias is due, in part, to the fact that the majority of people will likely be marginally informed, at best, about most issues, and the vague impressions they have will have been mostly informed by dominant discourses. So, while a particularly impacted community or field may hold intimate experience, expert knowledge, and higher stakes concerning a given issue, the opinion of an ill-informed majority—whose snapshot ‘opinion’ is no-doubt shaped by dominant discourse, which tends to be biased to favor elite opinion—will count just as much. Actually it will count for more, in the aggregate. Nonetheless, political elites can use the concept of ‘public opinion’ as a weapon—a weapon that is disguised as a mere measuring stick—to legitimize themselves, their agendas, and their powers.
While it may be foolish for political actors (including underdog challengers) to ignore popular sentiment, it is perhaps even more foolish to ‘chase after the wind’ of public opinion; to treat it as if it were something that existed concretely, as an unbending thing, rather than as an ever-constructed construction, whose articulation a political actor has to constantly contribute to and contest — if that actor hopes to be a contender, and not merely a commentator on the sidelines.
(Thomas Gilbert and Andrew Loveridge made interesting related points last year in the Berkeley Journal of Sociology.)