What early polling can – and can’t – tell us about 2013’s key US elections

Polls taken early in the election season are a most interesting phenomenon. The media loves them, while some think they are a waste of time.

The record shows that early surveys can tell us a lot about where a race will end up in the case of midterm House and even Senate elections. But in the 2013 elections, early polling is, at best, a very rough guide, and at worst, can tell us absolutely nothing. [cont.]

Harry Enten, The Guardian