Sure. As long as your voltage divider impedance is not too low and if my math isn't too far off...

Suppose the voltage divider is two 2K Ohms in series for the 2.5V, then the PIC's (approx.) internal 200 Ohm series resistance sourcing 5V will get you a little over 4.5V at the output.

But if it's two 200 Ohms in series then the output would only be about 3.3V.