Lattice QCD calculations of nucleon structure using pion
masses as low as 149 MeV will be presented. Because of work done to
reduce excited-state contaminations, the results agree with experiment
for four key isovector observables: the Dirac and Pauli radii, the
magnetic moment, and the quark momentum fraction; however, a discrepancy
remains for the axial charge, and evidence suggesting a likely cause
will be shown. Understanding these sources of error helps to increase
confidence in predictions of the tensor and scalar charge, which will
also be presented.