They believe in Christ, kinda. In reality many of them follow an odd indian pagan infused version of Catholicism. It comes complete with Mary in a cave outside of Mexico city, those day of the dead death cults, and many odd theological add ons that a traditional Bavarian catholic would find very strange.
Easter in Tucson we always went to the Pascua Yaqui Indian village which used to be at Grant and I-10.
Watched the Passion play with the Deer Dancers, and the Chapeyekas as they danced past the Evil Roman Soldier spirits.
Then we would head to our usual Episcopalian Easter Sunday services.
(Pregnant pause)
To say that we were participating in the same religious holiday was one of the most jarring disconnects in my childhood.