I've been looking for this clip from 'Yes, Prime Minister' for a while -
it shows how easy it is to get the answer one wants in an opinion poll, entirely based on the questions one asks. The discussion in this one is about mandatory military service, but it holds true on a number of topics. 'Yes, Minister' and 'Yes, Prime Minister' was a great BBC series, that I would highly recommend to anyone interested in politics.
Yes, Minister/Yes, Prime Minister 2-Pak - Amazon.com
Yes Minister & Yes Prime Minister: Complete BBC Box Set - Amazon.co.uk