Nord, they were the original species of Men, and should, in my opinion, be the only ones that have access to that power.
Actually, no. the Nedic from Atmora were. Bretons, Imperials and Nords more-or-less came about the same way, as slight evolutionary divergence based on their geographic areas. Bretons might be the wierd one. being a mongrel race of Nedic and Aldmer. If we assume Earth-biology, Bretons would be sterile, like all Hybrids, where as Nords and Imperials would be about as different form one another as the Swedish are from the French.
From what I understand of the origin of the races, there are fewer actual species than the 10 races. There's Mer(Chimer/Dunmer, Altmer, Bosmer, Orsimer) Men(Imperial, Nord) Yokudans(Redguard), Argonian, Kajhiit and the Hybrid Bretons. So that's six?
By that logic, Nord and Imperial would be the most likely candidates, if it's some sort of "Bloodline" thing. The Septim line were Dragonborne, so the original Kings (Skyrim) and the Cyrodiils are equally plausible.
But I played an Imperial Neravarine, so who knows the gods' will?