Engine cranks excessively before starting
 

I have a 01 Ram 1500 5.2 with 261k hwy miles which runs like a top except it cranks excessively before it starts? It will start right away if you restart it? I have tried differant
starting techniques like depressing the gas pedal which sometimes helps and once in awhile it will start fine on it's own? I have owned this truck for 9 mos. and love it. :)