It's a push for some, especially the BGN teams this week since the race was delayed at Rockingham and they need to be in Vegas tomorrow morning.
As boB and others have said, with a two driver team it is done all the the time. Over the road truckers face these types of logistic problems constantly. It's just part of the deal.
Even for the BGN boys with only one hauler, they leave Rockingham sometime Monday aft and likely at the shop by Monday night. The drivers grab some sleep and the team members unload and load the hauler during the night. Sometime around midday on Tuesday they should be ready to roll.
Figure its about 2200 miles from Charlotte to Las Vegas so that is around the average distance that needs to be covered. The weather this week is messing up the trip bad, but that is part of the deal as well sometimes. Anyways, a two driver team should be able to cover the distance in 38 to 44 hours. That will get you to the track on time, I think check-in starts around 9 AM on Thursday, which is 48 hours from Noon on Tuesday in Charlotte.
To a pro, it tighter than you would like, but very doable.
This week, the Winston Cup folks have two full additional days to get the trip done, piece of cake.
As to losing a hauler and contents for whatever reason. You just do what you can. Depends entirely on the teams circumstances regarding equipment and personnel. Like boB said, it has happened before.
If ya go over to NOL, there is an article about the troubles the weather is causing this week, plus some timeframe info on the trip.