My journalistic friends know I put very little faith in polls--and the polling in Iowa demonstrates why.
Assuming each and every poll was accurate (a very large assumption) within their various stated limits, consider:
6 different candidates have led the polls, often 2 within the same week.
At various times there have been swings of 10-15% in a very short period of time.
Some polls did not even give us the Margin of Error (MOE) which I consider essential for any understanding of their accuracy. (CBS aired a poll with a 6% MOE. Ridiculous. This means a very small sample and a very large margin of error, so large it shouldn't have been used.)
In my own thinking a 4% MOE is as large as should be used. Here's why: Come the general election and a close race (and I have seen this in the past) Candidate A has 52%, Candidate B has 48% with a 4% MOE. This means: (1) a possible complete reversal. B could have 52%, A could have 48% and thus a completely UN-trustworthy poll. Thanks; just what we need. (2) and the actual spread is from 44% to 56%. (see sentence just before (2).
Then, Iowans "vote" this week (they really don't, it's a caucus system, very much less accurate than voting at polls, and subject to great pressures), and yet, as many as one-third of Iowans still haven't made up their minds, and about an equal number say they could change their minds between now and the caucus!
That even further imperils the accuracy of the polls so far. If they don't know or that many may change, why should we believe what they are telling the pollsters???
In short, the only poll worth taking is the one taken election day; and I mean in the polling booth--forget exit polls, whose alleged MOE is even worse and much subject to disbelief and inaccuracy.
And having said that election day is the only good poll, don't forget Florida and "hanging chads". Remember?
Oh yes, after Iowa comes New Hampshire and more polls you shouldn't believe in a state that is about as UN-typical as an American state can get. It is a helluva way to elect a president; and don't get me started on the worse feature of all: the inaccurate, UN-democratic, UN-fair but UN-fortunately LEGAL electoral college method of electing presidents.
I'm just sayin'...