  Recent lattice calculations have confirmed that QCD static potential for
sources in different representations of the gauge group is proportional to
eigenvalue of the corresponding quadratic Casimir operator with an accuracy of
a few percents. We review the present theoretical status of the "Casimir
scaling" phenomenon and stress its importance for analysis of nonperturbative
QCD vacuum models and other field theories. It is argued that Casimir scaling
strongly advocates the property of Gaussian dominance and we propose different
lattice tests to improve our understanding of these phenomena.
