Snaking a new cable is difficult to explain on an internet forum, even more so when you're dealing with a 1/2 foundation wall with another wall setback from it. Although construction methods vary, often there is no way to snake from your lower wall to the upper because the upper is built directly on top of the protruding foundation. Like Oso says, it may be easier to get a cable down from above then to get one up from below.
Another method is plastic or metal channel that can be mounted to the wall to direct the power (and another for cable connections) from where they are to where you need them to be. Those are available at most home centers.