We propose a systematic way to search for the location of the QCD critical point in relativistic ion collisions, based on the relation of intermittency in momentum space to finite-size scaling (FSS) in configuration space. This relation is valid for systems equilibrating within the FSS region. The key ingredients of our method are combined measurements of the intermittency index $\phi_2$ in transverse momentum space of protons produced in central A+A collisions and of the corresponding freeze-out parameters $\mu_b$ (baryochemical potential) and $T$ (temperature). We demonstrate how the proposed method works in practice using NA49 data for central Si+"Si" collisions at $\sqrt{s}=17.2$ GeV. Based on these data we extract a set of predictions, concerning reachability of the critical endpoint, for the running NA61 experiment at SPS (CERN).