  We explore a dark matter model extending the standard model particle content
by one fermionic $SU(2)_L$ triplet and two fermionic $SU(2)_L$ quadruplets,
leading to a minimal realistic UV-complete model of electroweakly interacting
dark matter which interacts with the Higgs doublet at tree level via two kinds
of Yukawa couplings. After electroweak symmetry-breaking, the physical spectrum
of the dark sector consists of three Majorana fermions, three singly charged
fermions, and one doubly charged fermion, with the lightest neutral fermion
$\chi_1^0$ serving as a dark matter candidate. A typical spectrum exhibits a
large degree of degeneracy in mass between the neutral and charged fermions,
and we examine the one-loop corrections to the mass differences to ensure that
the lightest particle is neutral. We identify regions of parameter space for
which the dark matter abundance is saturated for a standard cosmology,
including coannihilation channels, and find that this is typically achieved for
$m_{\chi_1^0}\sim 2.4~\mathrm{TeV}$. Constraints from precision electroweak
measurements, searches for dark matter scattering with nuclei, and dark matter
annihilation are important, but leave open a viable range for a thermal relic.
