Yes it is possible. There is a plugin for VC called hook that could be used to generate an event based on certain keyboard combinations, or you can use eventghost with a number of different remotes to send an event to VC.
What kind of remote do you have, and do you use any special software with it?
But remember, you can still use a voice command to tell VC to listen, but you do it from standby mode, not from off mode. It sounded like that is what you wanted.