The head of the U.S. Postal Service said in an interview that the organization will default -- perhaps as early as this winter -- unless Congress intervenes. Postmaster General Patrick Donahoe's comments reflect a well-known reality that the Postal Service is in dire financial straits. The rise of email and online bill-paying has steadily eroded its profits over the years while labor costs soar. Donahoe is calling for a host of changes, including the elimination of Saturday delivery, to close a deficit projected to top $9 billion this year. But he said Congress needs to step in to help keep...