1. A cardiac pacemaker, comprising: first and second pacing channels, each such channel comprising an electrode for disposing near a chamber of the heart, a pulse generator for outputting pacing pulses, and a channel interface for adjusting the pacing pulse energy; a controller for controlling the operation of the pulse generators in accordance with a programmed pacing mode; an evoked response sensing channel comprising an electrode and a sense amplifier for sensing an evoked response generated after a pacing pulse; and, wherein the controller is programmed to: deliver first and second pacing pulses from the first and second pacing channels, respectively, to one or both of the paired atria or to one or both of the paired ventricles during a cardiac cycle; record an evoked response waveform from the evoked response sensing channel; correlate the evoked response waveform with template waveforms representing capture by both pacing pulses, capture by the first pacing pulse, and capture by the second pacing pulse; and, classify the evoked response as representing a type of capture represented by a template waveform if the evoked response waveform highly correlates with one template waveform and has correlation values with the other template waveforms within specified bounds.