susan- my only experience with wintering them over is to put them in a greenhouse set-up I have in a huge laundry room here. I never let the temp get below about 60 degrees in there but usually keep it around 72 degrees most of the time, and lights are set to timers for at least 8 hours a day. The humidity isn't as high as it would be here in the summer, but running the washing machine several times a day apparently gives them just enough moisture in the air. They were blooming during Christmas last year indoors with this set up. Because I didn't want them to put on any growth, I didn't fertilize until they were re-settled out in my garden, kept them pinched and it worked okay. I also dig up a lot of small volunteers this time of year and haul them in too. I only watered when the soil felt dry. Good luck with whatever you decide to do!
-Nan