Variational transition state theory is used to compute the rate of nonadiabatic electron transfer for a model of two sets of shifted harmonic oscillators. The calculations provide new insight on the suitability of the energy gap as a reaction coordinate. The relationship to the standard generalized Langevin equation model of electron transfer is established, and provides a framework for the application of variational transition state theory in a realistic simulation of electron transfer in a microscopic (nonlinear) bath.