  Gluon, ghost, and quark propagators are computed in the Schwinger-Dyson
formalism. The full set of one-loop and two-loop contributions to the gap
equations are evaluated for the first time. A new and efficient method for
dealing with quadratic divergences is presented and a consistent
renormalization method is proposed. We find that the two-loop contribution to
the propagators is subleading, good fits to lattice data are possible, and
reliable vertex models are important to obtaining desired ultraviolet,
infrared, and gauge-symmetric behavior.
