This article explains the steps to delete a contract request in the OCM module.
To delete a contract request, it must be in either Draft or Rejected status. If your request is in Pending Approvals or Submitted status, you may withdraw the request back into Draft status by going to the Review & Submit page of the request and click the "Withdraw" button.
Once the request has been changed to Draft status, return to the page that lists all your requests and find the red trash can button in the far right column. Clicking this button will permanently delete the contract request.
UPDATE:
You now have the ability to delete the contract request another way. When you are inside the contract request, in the top right you should see "Delete this Request."
When you click on Delete this Request," you will be prompted to confirm that you want to dele the contract request. Click OK if you do.