The polls this far out from an election 3 years away, are of limited value, yes. Nevertheless, they are very useful in telling potential candidates, what their weaknesses are with voters, giving them enough time to work on any perceived weaknesses that voters think they have. Thy also let potential candidates know who their biggest opposition will be, why voters like those other candidates, and what they need t do to prise away voters from those candidates.
That is very true of honest, unbiased polls.
Unfortunately, at this point all the polls are essentially push polls funded by those that have a need to manipulate the voting public.
Honest scientific polling for the 2012 election will begin in the spring of 2012, when honest people will be willing to spent their money on real data.
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