To answer the question more accurately:
AA upgrades are 30,000 miles r/t and anyone can request them. CO upgrades are also 30,000 miles roundtrip - elites can request them on all fares, non-elites can only request them from selected fares (starting right now at $623 - pretty high).
I can tell you that CO domestic mileage upgrades are virtually always no problem for elites. I also have had good success with AA mileage upgrades as an elite.
UA also flies this route, but I have never upgraded it.
I prefer upgraded CO to AA on this route, but, as discussed, CO can be an expensive upgrade for a non-elite.