In this talk, I will present a new mechanism to generate a coherently oscillating dark vector field from axion-SU(2) gauge field dynamics during inflation. The SU(2) gauge field acquires a nonzero background sourced by an axion during inflation, and it acquires a mass through spontaneous symmetry breaking after inflation. Then, the coherent oscillation of the dark vector field can account for dark matter in a wide mass range, evading some constraints in the usual misalignment production scenarios. In this scenario, one of the dark vector fields can be identified as the dark photon. Finally, I will also discuss some phenomenological implications.