Imho
Ladainian Tomlinson probably comes closest but he seems to have peaked early even for a great RB and he is no Barry Sanders at any rate. Injuries the mortal enemy of all running backs have taken there toll on LT.
Honorable mention but a long way from Sanders - Clinton Portis.
Adrian Peterson has the potential to be a really great one but he has only played 30 NFL games, so the jury is still out before I can call him better than even Tomlinson.
One more season like the one he just had and yeah he is the most exciting RB since Barry.
wil.