You should be able to. Pelargoniums are able to tolerate light frosts easily and often winter over in my climate as well. You will still want to cut it back pretty well in spring and repot with fresh soil.

I lived in northern CA for 60 years. We had the simple non-shaded (non-zonal) leaved pelargoniums growing continually in ground from before I was born for perhaps 40 years until we got two days of ~15° F when they were wiped out. Potted plants are far more exposed and the fancier plants also seem less hardy, but you might consider establishing them in ground.

Yeah I would place it by the house, and cover it well on frosty nights. This is in zone 5b in the greenhouse yesterday. It's been through a few hours of 34-36F at the end of Dec.

They do amazingly well in the ground in zone 9b. Put them in the ground and don't worry about protecting them from frost - they don't need protection from frost.