Spiritual power and blood are related, in that spiritual gifts can be passed down.
The generation of these powers is however active. This means, they can be relinquished if they are not worked upon. Therefore, from India to every civilization, we have stories about the "Fall of the Aryan", not necessarily so much related only to race, but also the spiritual power falling. Hindus of the spiritual class still follow these warnings.
Every Gentile can develop spiritual powers as all beings have this by birthright, and this knowledge was given to us by the Gods. It's no different in a sense, than gymnastics. You can be gifted, but another will be better if they train and you don't train. In some way, it is like muscle mass. You work it, you'll have it. You don't, you don't have it. You may have natural gift but it can go that far without being trained.
Whites have a good predisposition for working these powers, but so do Asians, and so have Blacks who may for example generationally worked on this. Spiritual powers are parts of being human. Asians that could set things on fire with pyrokinesis, walk on walls, and do other tremendous things, are proven to be doing just that. The same goes for people in India. The same things were done in White cultures by other initiates. Egypt was top tier in these things.
Most Whites right now are lazy and generally don't work on these powers, but previous generations did. So leftovers are still there. But if this downtrend continues, a day will come where these will sink lower.
Yes, different Races have differences at the soul, but it is not something like another species altogether. These fine differences go a long way in the spectrum of life and therefore should be preserved.