There are now two bulls in the 2012 rut. The first "Twin Forks" has a good chance of surviving challenges as a herd bull. The second, "Little Fork" probably will not make it long term. Yesterday the elk rut began in the morning on the south end, in the evening a second bull entered the rut on the north end.
The first bulls that show up in the rut often are small and later become what are termed "satellite bulls". Satellite bulls hang around the edges of herds and are smaller than the dominant herd bulls that have much larger bodies and antlers. According to research, satellite bulls actually breed more than herd bulls that spend most of their time running them off. You can see this if you watch the herds closely.
Typically the very biggest bulls show up late in the September and take over. All elk are big, but herd bulls can be huge. It is interesting to watch this changing of the guard.
Bull fights will begin soon when the big bulls show up. I would rate the next month as the top period for seeing bull fights, although I have seen them up until mid-November. In this first few weeks of the rut dominance is established for the first time.