since a Nevada resident can have a Los Angeles area code on his cell phone, and cell phone prefixes aren't necessarily as determinative of the exact geographical location where you live, but even then, competent pollsters might be able to use billing info to do so.
Not to mention if internet polls get people using phones or mobile hotspots, which can give an IP address that is way off. My mobile IP corresponds with a town 146 miles from me, pretty far north. Not even close. Static IPs for cable/etc are more accurate but can have some issues from time to time as well.
