  We present a new class of Dark Matter (DM) models wherein the Standard Model
(SM) is extended with a new $SU(2)_D$ dark gauge sector. In this framework the
stability of DM is provided by the conservation of a $U(1)$ global symmetry,
which upon appropriate charge assignments for the $SU(2)_D$ multiplets,
effectively leads to a $\mathbb{Z}_2$ symmetry subgroup. The origin of the
global $U(1)$ symmetry which ensures the stability of DM can be justified in
the form of a dark EW sector or through an underlying composite structure. The
key ingredient of the model is a Vector-Like (VL) fermion doublet of $SU(2)_D$
, the members of which are singlets of the SM Electro-Weak (EW) gauge group,
which mediate the interactions between the dark sector and the SM, via new
Yukawa interactions. This class of models, labelled as Fermion Portal Vector DM
(FPVDM), allows multiple realisations, depending on the properties of the the
VL partner and the scalar potential. After spontaneous breaking of the
$SU(2)_D$ symmetry via a new scalar doublet, the ensuing massive vector bosons
with non-zero dark-isospin are DM candidates. The new class of FPVDM models
suggested here has numerous phenomenological implications for collider and
non-collider studies. As a practical example, we discuss here in detail a
realisation involving a VL top partner assuming no mixing between the two
physical scalars of the theory, the SM Higgs boson and its counterpart in the
dark sector. We thus provide bounds on this setup from both collider and
astroparticle observables.
