the other entries were the Züst representing Italy, three cars (De Dion-Bouton, Motobloc, and Sizaire-Naudin) representing France, and Thomas Flyer competing for the United States
Update Aug 16th: I just found the OldMotor.com has posted a photo taken during the race while they came through Ogden Utah: http://theoldmotor.com/?p=9927
read about the passenger, he was hired by each of the great race entrants to guide them from Ogden Utah to Nevada, as he had been a surveyor for the railway