Agreed with all of the above. I, too, live in 6b; Southeast Missouri to be precise. I have grown all of my Sarracenia outside in previous winters with minimal protection... some with none at all. Not to say it didn't make me a bit nervous during our cold dips. I have yet to loose one to cold temps, though. This includes S. flava, S. leucophylla, S. rosea, S. psittacina... basically all of them.
That said, it makes a difference whether they are potted or not. Mine are typically potted, thus my regular yet slight anxiety during cold dips in temperature. I am experimenting with keeping everything in the garage this winter to see if it affects their spring growth, however.
I can cover them in newspapers and then put a tarp over that though.