Weak Brakes

[phychotron]

My brakes have been feeling really weak recently. It comes to a stop but when at a low speed at full pressure it still slowly creeps to a stop, not locked up or anything--the bottom half of the pedal doesn't seem to add any stopping power. I pump the hand brake to adjust the rear brakes and it seems to add a little bit of stopping power but doesn't quite solve the problem. I was wondering which part this sounds like is failing. I have the rear wheel cylinders/shoes/springs but havent put them on because the back looks good. New rotors/pads on the front 15k ago.

9478