As a GM, if you're up front, you get 3 bags at 70 pounds. If you're all up front, everyone except the infant gets 3 bags at 70 pounds. You don't mention your fare class or if you're up front or in the back, so up front would obviously be the best case scenario. And if you clear prior to departure, you get the baggage allowance.

If you're in coach.....

You get 2 bags at 70 pounds as a GM. (see 4th bullet under Checked Baggage Exceptions in the link below)

If you've got a Delta AMEX and your wife is an authorized user with her own card, she can check one 50 pound bag for free and so can your daughter since they're on the same PNR.

With those qualifiers, that's at minimum 2 bags at 70# and 2 bags at 50# plus carry-on items for 3 people. And all of this is only if the TA says you can't check their bags because of the separate PNRs.

Good luck! ^

Delta Baggage Allowances