It all has to do with your IP address which is essentially your street address on the super information highway. High speed providers usually give you a static IP address (your's is 216.89.227.196). Dial up providers usually use a set of rotating IP addresses since users are more likely to connect and disconnect frequently. This way they need fewer available IP address since they can just assign one that's not being used to a connecting user.

I believe the poll looks at your IP address and determines if you've voted or not and if it's already seen a response from that IP, it denies the user. So if you are using a dial up and your IP address is dynamic (not static) you can vote multiple times.

I agree that any results obtained through forum will be a bit skewed because there's probably a limited range of folks that participate online...how else could we go about it?