In my personal opinion there is no such thing as Christian Wicca.
Wicca is a very specific religion with specific beliefs and practices which in no way match the beliefs and practices of Christianity. Wiccans do not acknowledge Christ as the Savior, do not believe in the concept of Original Sin or of sin at all, believe there is more than one God, and believe that we do not need to be "saved."
One can take bits and pieces of Wiccan belief and of Christian belief and combine them I suppose. But what you have afterwards is neither Christianity nor Wicca.
What most mean when they use the term "Christian Wiccan" is someone who is a Christain who practices magic. That means that a more accurate term would be "Christian Witch" as Witchcraft is not a religion but rather a magical practice.
By the way, you don't have to be Wiccan to practice magick and spells. In fact most Wiccans I know rarely if ever cast spells.