Distributed communications systems providing and supporting radio frequency (RF) communication services and digital data services, and related components and methods are disclosed. The RF communication services can be distributed over optical fiber to client devices, such as remote units for example. Power can also be distributed over electrical medium that is provided to distribute digital data services, if desired, to provide power to remote communications devices and/or client devices coupled to the remote communications devices for operation. In this manner, as an example, the same electrical medium used to transport digital data signals in the distributed antenna system can also be employed to provide power to the remote communications devices and/or client devices coupled to the remote communications devices. Power may be injected and switched from two or more power sources over selected electrical medium to distribute power for power-consuming components supporting RF communications services and digital data services.