The vacuum-driven nonperturbative factors L-i for quark and gluon Green's functions are shown to define the nonperturbative dynamics of QGP in the leading approximation. EoS obtained recently in the framework of this approach is compared in detail with known lattice data for mu = 0 including P/T-4, epsilon/T-4, epsilon-3P/T-4. The basic role in the dynamics at T less than or similar to 3T(c) is played by the factors L-i which are approximately equal to the modulus of Polyakov line for quark L-fund and gluon L-adj. The properties of L-i are derived from field correlators and compared to lattice data, in particular the Casimir scaling property L-adj = (L-fund) (C2(adj)/C2(fund)) follows in the Gaussian approximation valid for small vacuum correlation lengths. Resulting curves for P/T-4, epsilon/T-4, epsilon-3p/T-4 are in a reasonable agreement with lattice data, the remaining difference points out to an effective attraction among QGP constituents. (c) 2007 Elsevier Inc. All rights reserved.