In an American race, you need to be the best to get someone to sponsor you for the next race. However, not being the best doesn't mean that you are banned from racing in other races. It just means that you need to use your own money for everything.
This game will let you feel how it’s like in the real world. At least, in the world of racers as you would need some sponsors to make sure that you can buy all the necessary parts that you need to max out the speed of your car without being bankrupt.