Looking at the
Earn OnePass Miles page for Alaska, I would read "Earn OnePass miles with standard fares on Alaska Airlines" along with "Travel Area for Mileage Accrual: All Alaska Airlines-operated flights systemwide" to mean that to earn credit it has to be an AS fare, operated by AS.
However, I'm hopeful that this has been interpreted to mean that you simply have to fly on AS metal, and can use a DL fare. Anyone know the answer?