… Most polls that purport to provide Iowa caucus results simply ask each interviewee whether they are likely to attend a caucus. The tendency to say yes yields responses so highly inflated as to be worthless. …
Unlike public pollsters, campaigns pay substantial sums to purchase lists of previous attendees and expend vast efforts assessing who the new participants might be. They then lavish millions on that segment — phone calls, mail, door knocks, invitations to meet the candidate, etc. — rendering these individuals an entirely different species from the ordinary Iowa registrant. CONT.
Mark Mellman (Mellman Group), The Hill