This is the most important factor, in my opinion, in the way the internet is changing the world. For one thing, newspapers are losing (not loosing) subscribers, TV news is losing viewers, and caller ID is causing people to not answer their phones. Times are changing, and the media is still acting like this is 1970.
I know that I haven't been polled ever in the last 15 years, but then I never answer the house phone, and I only have a house phone for emergencies. Everyone I need to talk to calls my cell. Pollsters don't call cell phones that I have ever heard of. I also don't watch TV, and I only read the local liberal rag when there is absolutely nothing else to read. I get all my news at FR first (thank you).
This can only get worse for the pollsters with their mid-20th century methods.
My house phone rang last evening - the caller ID said "Quinnipiac" - - - since they do lots of polling in PA, I thought, yes, at long last, I get to be polled - - - so I pick up the phone and say "Hello" and the girl says "Sorry, wrong number" - - - it was like she could tell I was FReeper by my voice!
I think another important factor is the large number of people who now vote absentee. I understand that now almost as many people vote absentee as vote in the general elections. Absentee voters will favor Republicans somewhat. I understand the requests for absentee ballots in CO have heavily favored Republicans. I have already voted myself. I think we all may be surprised at how well the GOP does this year.