Instead of running speaker wire directly to rear speakers. Can I run speaker wire into an amp then go from amp to speakers? Obvious reason is to provide rear speakers with more power. My amp has RCA and speaker wire inputs.

I wonder why you would need that extra amp. I suggest using the leveling controls on the unit to get your balances correct. The surround speakers are not designed to take high power. I have found that using the "all channel" setting on the remote levels out the sound on all the speakers. If you still want to do what you are asking, make sure to run the input into the AUX input of the amp. It's the most protected and will help prevent a catastrophe. Please note that I am not a professional in this field and I offer the suggestions based upon my own experiences and mistakes. It's all about the sound baby!