Yes, you should be able to cancel the contract since you have not taken delivery of the vehicle. You will have to review your contract carefully to see what the cancellation provisions were, if any. If you made a good faith deposit (money down) already, then you may end up losing that deposit. It all depends a lot on the contract and how much you are willing to fight over it. Worst case scenario, get a lawyer to review the contract and see if there is anything in it that can be used to nullify the contract.
I am not a lawyer, however, so here is a link to the American Bar Association publication about this question:
http://www.abanet.org/publiced/practical/carcontract_cancel.html
Best wishes, and don't let that car dealer jerk you around!

