Yes, for two reasons.
First, it shows that you were considered highly competitive by 2 MOCs. (In fairness, for some sparsely populated states, this may not be as important b/c sometimes there are very few qualified candidates so it's not as uncommon for someone to get multiple noms). But, generally it's a good thing.
Second, it gives USNA more flexibility in slotting you for an appointment as you can be assigned either to the Rep or the Sen (or another source).