The more senior FOs that wanted to get to ORD have seemed to finally all be there. I foresee it will honestly be a greater chance of you getting assigned ORD. Depending on your seniority in the class, you definitely could still get DEN out of class. Now, the upgrades are all going to ORD, so that will open spots in DEN since the upgrades are mostly coming out of DEN. These vacancies will be filled with new hires. You might have to be patient, but as an FO I see you being able to hold DEN. It will get much harder once our next base opens. My own opinion, after seeing some forecasts and other things recently, the announcement for this base is coming by July at the very latest with filling it by Sept to Oct as airplanes are coming soon.
As a Capt, I hate to say it, Dream on buddy for a DEN base any time soon (relatively speaking for when your upgrade comes.). There are sooooo many upgrades that are having to leave for ORD, not to mention when we open the next base, it will just take forever to get people back. I can definitely see people never being able to get back to DEN, depending on the age you are at at upgrade.
There is my long-winded OPINION of an answer. But, Congrats on the job! It is great to see so many excited people, just like myself, that are coming here!