Found on http://www.autopuzzles.com/
Original photos of this Protos at the start of the race: http://justacarguy.blogspot.com/2011/03/new-york-to-paris-race-of-1908-great.html
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
If the rally race cars of the Paris to Peking, and the New York to Paris races interest you too, here are the Spyker http://justacarguy.blogspot.com/2011/07/1907-spyker-charles-godard-and-jean-du.html
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