Idle video-on-demand (VOD) and/or other streaming media channel capacity is used to deliver promotional content to selected set-top boxes (STBs) in a cable television network. Commercial segment cues are used to instruct a set-top box to switch away from a broadcast program to the streaming media channel during a commercial segment, and then switch back again to the original broadcast program at the end of the segment.More particularly, a promotion server determines an asset to be distributed such as a targeted promotion item (e.g., a commercial), and a list of STBs that are to receive it. The promotion server causes the video promotion content to be stored in VOD/streaming media servers located at the head ends. A scheduler process then delivers schedule messages to head end message servers which identify each promotion asset, and an STB which is to receive it. The head end message server notifies its associated VOD/streaming media server which then cues the asset by loading the asset, starting the asset, but pausing it. Prior to the occurrence of a commercial slot in a broadcast program, an asset trigger is inserted into the broadcast stream at the head end. This asset trigger contains general information concerning the asset to be sent, and an idle VOD/streaming media channel number. The STB receives the asset trigger and readies itself to tune to the VOD/streaming media channel when cued for at the beginning of a commercial segment, but does not yet tune to the VOD/streaming media channel. Upon detection of a commercial cue tone in the broadcast channel, the head end message server sends a tune away trigger to the STB, and also instructs the VOD/streaming media server to start playing the cued promotion. When the STB receives a tune away trigger, it switches from the broadcast channel being played to the selected idle VOD/streaming media channel, and the promotion is viewed.