There are no non stop flights on AA between the DC area and LAS. Whether you fly from DCA or IAD, you'd have to connect in DFW, ORD, MIA, JFK or LAX. Even if you get on a flight from your home airport to one of these hubs, there is no guarantee that you'd get on the flight from there to your final destination. In other words, you can get stuck at an airport en route.

Space available travel on the Monday after Thanksgiving is just as bad as on the Sunday of Thanksgiving weekend.