  The Next-to-Minimal Supersymmetric Standard Model (NMSSM) provides a natural
framework to realize a low-scale supersymmetric (SUSY) model, where a singlet
superfield is added to the minimal model to generate a SUSY-scale higgsino mass
term with its vacuum expectation value. Due to the presence of the extra
singlet field, the vacuum conditions to realize the correct electroweak
symmetry-breaking become fairly restrictive especially if we impose
universality conditions at the unification scale. In this paper, we show that a
non-universal gaugino mass spectrum can significantly relax this restriction
even though the scalar masses and trilinear couplings are subject to
universality conditions. With the gaugino non-universality, we find that
higgsino can be the lightest SUSY particle and its thermal relic abundance can
reproduce the observed dark matter density in a wide range of parameter space
in which the 125~GeV Higgs-boson mass is obtained. This higgsino-like dark
matter may be probed in direct detection experiments. We also find that there
is an upper bound on the masses of supersymmetric particles in this scenario,
and many model points predict colored particles such as gluino to be within the
reach of a future 100~TeV collider. Implications for no-scale/gaugino-mediation
models are also discussed.
