The 4 hour connection time is irrelevant in this case.

The pax has a 1am flight from PDX-MSP. Unless there is another NW flight that leaves between 12:01am-12:59am there is no possible way to fly standby for an "earlier" flight as they are not the same day. This would require a change fee and difference in fare price.

That's why whenever you book a redeye you should try to get the one that leaves right before midnight, that way you have the chance to fly standby.