  We investigate the physical spectrum of vector-like SU(N) gauge theories with
infrared coupling close to but above the critical value for a conformal phase
transition. We use dispersion relations, the momentum dependence of the
dynamical fermion mass and resonance saturation. We show that the second
spectral function sum rule is substantially affected by the continuum
contribution, allowing for a reduction of the axial vector - vector mass
splitting with respect to QCD-like theories. In technicolor theories, this
feature can result in a small or even negative contribution to the electroweak
S parameter.
