I simply think that stock car racing is the best outlet for American racing talent. Compared to the costs of running an entire karting formulae and then the junior formulae, running through the junior ranks of stockcar racing is a lot more economically sound. So what ends up happening is that the best talents go to NASCAR instead of being divided up into the various classes of European motorsport. So, making a switch doesn't seem extremely farfetched.
As for drivers that could make it, Jeff Gordon by far. A few years ago when Gordon was dominating NASCAR, it was rumoured that GM was interested in F1 and that Jeff Gordon would be plucked from NASCAR to run the European junior formulae in preparation for an F1 debut. However, GM pulled the plug on the project when they realized the increased sales that an F1-Gordon combo would have brought in were already being brought in by NASCAR-Gordon.
I think that Jeff will eventually run Indy as well as endurance races later in his career. I also thought the late Dale Earnhardt would have eventually ran Le Mans. His driving at the 24hrs of Daytona was quite inspired and I think he would have made a good transition into running GT cars (and I wouldn't have put it by him to run the prototypes either).
I also think that either Gordon, Rusty Wallace, or Ricky Rudd would have a wonderful go at touring cars. All three are the best road racers NASCAR has to offer, and if Jason Plato ever makes the jump to NASCAR successfully, why wouldn't such a switch go both ways.
I could also be really cheap and mention Mario Andretti (he has won Daytona)
