Truck Repair: Engine wont start, electric fuel pump, dodge diesel

Question
I have a 2004, 2500 Dodge diesel.  It has about 76k on it.  Over the past 2-3  weeks it has been more and more difficult to start.  One day it took 15 - 20 seconds of cranking and would finally fire up.  The next day,I went to start it in the morning and it would crank but would not start.  The problem seemed to get progresivly worse until it would not start.  What could cause this?  

Answer
There is an electric fuel pump on the fuel filter may be bad.We dont get to work on the new common rail Dodge thanks to some Einstein from Cummins agreed to make it where Cummins could not hook there communication software to it like the older 24V engines.