If a project has not received any fan contributions, it can be canceled and deleted. 

To cancel and delete a campaign: Go to My Projects to view a list of your projects.  If the project is not yet live simply click on the "cancel and delete" link.  If the project is currently live and visible you must first revert to draft mode by clicking the edit link and choosing the "draft mode" option on the basics page. Once in draft mode, navigate back to the "My Projects" page and the "cancel and delete" link will now be visible if no fan contributions have been made.