Some cd players have 3 pre-amp outs , and some have just 2. If you just have 2 outputs chances are your CD player is going to shut the internal amp off if it senses you have RCA's connected to the unit (my clarion did this) In that case you wouldnt be able to. Only way you'd be able to improvise is if you ran once rca to your amp(off of the rear outputs), then used Y-connectors and filled both front/rear inputs on the amp.
Then you could still use the front outputs on the cd player's internal amp and use them to power the rear speakers. Your Fade would be messed up but the bass would be in the right place