Marriott is linked with United. So you can't link your Delta account.
However if you have a SPG account, you can link that one.
The above link will give you more info on SPG/Delta
Hi email@example.com and seatexan,
There are actually over 40 different airline programs you can choose from when setting your Earn Preferences to Miles in the Profile section of your online account, including Delta SkyMiles. Check out the following link for a list of these airlines and more info: https://www.marriott.com/marriott-rewards/earn/miles.mi
seatexan - Might you have been thinking of the RewardsPlus program?
Yes! that is what I was thinking! Thank you!
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