We consider contests with a large set (continuum) of participants and
axiomatize contest success functions that arise when performance is composed of
both effort and a random element, and when winners are those whose performance
exceeds a cutoff determined by a market clearing condition. A co-monotonicity
property is essentially all that is needed for a representation in the general
case, but significantly stronger conditions must hold to obtain an additive
structure. We illustrate the usefulness of this framework by revisiting some of
the classic questions in the contests literature