Great poll! It would be interesting if you could have some follow-up questions to see if they are being truthful or are they just fooling themselves. Most people have no idea how much they actually have at home and will give the "right" answer so as not to sound unprepared, stupid, wrong, etc. It's typical of almost every survey ever conducted, kind of like people telling you what you want to hear. How are they actively working towards preparedness? What have they done this week in that direction? What method is their means to make drinkable water? Have they actually tried this method?
I like to ask people what they would do after a hurricane (I live in Houston, TX) when the power is out for a week. When they stumble around and don't have a good answer then start going in the direction of "Well FEMA is going to come and...", I say one word - KATRINA! Then they get this panicked look and I just shake my head. They don't want to acknowledge the fragility of their existence so they live in a delusion that everything's going to be OK. Sad isn't it!