Any good poll accounts for people who won't pick up the phone. Otherwise you might as well not poll.

As for the 4%, that's why I said it's a bigger number than I'd have picked. There is probably a perfectly reasonable answer as to why it is 4%. I just gave you one example but it's easy to tink of a few other scenario's: poverty, lack of internet availability in rural areas, the exact wording of the polling questions, etc. It's not my poll.