So, the easy answer is No, you can't.

Additionally, on most US domestic routes, especially on busy travel days the list even three hours out is often far different to the list 35 mins before boarding. Many GS' and 1K's won't admit it but they love showing up at the gate for a flight they are not on, getting waitlisted for the flight, then the upgrade, and watching their name pop to the top of the list.