It is no longer a simple question, as more people become “unchurched” and the United States becomes even more diversified, there is a larger population that celebrate the holiday as a nonreligious holiday — an opportunity to party and give gifts.
I also think most churches find their attendance grows around Christmas (which has been true for many years) with those wishing to touch the spiritual roots from which Christmas grew. The most interesting part of this phenomenon is that the roots of the celebration of Christmas at this particular time of the year go back to pagan celebrations during which Christians could celebrate the birth of Jesus without standing out and, therefore, being even more persecuted than they already were.
The celebrations of light in many forms are on the rise and even though many do not involve Christianity, it is a time when people take time out and contemplate life, purpose, morality, and the essence of being. The celebration of light, in whatever form, is the celebration of the dawn of human consciousness and the evolution of that
consciousness.