A novel adaptive statistical loop filtering technique is applied to the class of nonuniform sampling polarity-DPLL synchronizers. The objective of this innovative filtering approach is to improve the loop's acquisition performance at a minor cost of its steady state tracking behavior. The filter's adaptation mechanism is modeled as a finite state machine and its statistical performance characteristics are obtained by close-form solutions in terms of state transition probabilities. The fast switchover response from tracking to acquisition mode and vice-versa is numerically evaluated via first-order Markov chain analysis by hypothesizing short-time open-loop conditions. The analytical findings are verified by simulated results of a practical application, concerning multilevel excitation signaling waveforms.