We report a measurement of the forward-backward charge asymmetry
of electrons from W boson decays in p anti-p collisions at s**(1/2) = 1.96 TeV
using a data sample of 170 pb-1 collected by the Collider Detector at
Fermilab. The asymmetry is measured as a function of electron rapi+dity and
transverse energy and provides new input on the momentum fraction dependence
of the u and d quark parton distribution functions within the proton.