Abandon is effectively deleting on DotApprove, however, all abandoned jobs/ campaigns are kept in a tab in the details view within the job area for auditing purposes.  

To Abandon a job click on the 'Actions' drop down, and then select 'Abandon'.

 This will then prompt you for a reason the job is being abandoned. This must be filled in for the job to be abandoned.

Once a reason has been given the job will show as abandoned and will be located within the abandoned list.

Once abandoned, you cannot recover a job. Instead of recovering a job, you can duplicate the abandoned job. Read more about duplicating a job here.