Amy I live in zone7a in NC and have several clematis in pots that stay outside over the winter. If you are concerned about your clematis, you could dig a hole in the ground and sink the pot in the ground which will act as an insulator to help protect the plant. You could also bring the pot inside into an unheated garage during the really super cold parts of the winter. Like I said however, my clematis do fine outside in my gardening zone in containers and yours probably would also.

Since most Clems are hardy down to zones 4 or 5, I doubt even in a container that 7 is a problem.

The only thing I would possibly be concerned about with Kiri Te Kawana is that it is a type II. If the plant dies back, then the blooming of it next spring might be delayed if it died back to the crown. Generally speaking, I wouldn't be concerned with it either and provided some advice for assurances sake. You know people can be rather protective when it comes to their clematis! ;)

I live in zone 6A/B. Last year was the first year that I had bubble wrapped 8 pots of clematis. They sat out on my south east facing deck the entire winter and all survived.

Thank you all.
I have no ground to bury it into, but it doesn't stay all that cold for too long here. It's in a pot that's 12" in diameter, but only 11" deep. It probably will die back to the crown, since the plant itself is barely 8" tall. I wasn't necessarily expecting much growth, but will the root need more depth until it goes dormant?
Amy

Depends on how big the clematis was when you purchased it and how much it has grown since you potted it up. If you are planning on planting it in its permanent location, I would probably leave it in its current pot until next spring.

Oh, it hasn't grown much and, truth be told, I broke a couple of inches off the top while trying to get it tied to its stake "just right". It's small but happy; I'll let it stay put till spring.
Thanks again,
Amy

Sounds like it is good to go for this season Amy. Good luck!