If you call the above code repeatedly, this count may reach the backout threshold configured on the destination, at which point the messages will be re-queued and no longer available for receipt.

Senator Clinton is hoping to cut into Obama's lead in the delegate count with a victory in Pennsylvania, and is also hoping for re-votes in the large states of Florida and Michigan.

Now that they could re-count their outbound journeys, they were able to calculate the journey home.