We revisit a theory that proposes a dark charge, $D$, as a dequantization of the electric charge, $Q$. We find that the general arguments of anomaly cancelation and fermion mass generation yield both $D$ and $Q$, nontrivially unified with the weak isospin $T_i$ $(i={1,2,3})$ in a novel gauge symmetry, $SU(3)_C\otimes SU(2)_L\otimes U(1)_Y\otimes U(1)_N$, where $Y$ and $N$ determine $Q$ and $D$ through the $T_3$ operator, i.e. $Q=T_3+Y$ and $D=T_3+N$, respectively. A new observation is that fundamental particles possess a dynamical dark charge which governs both neutrino mass and dark matter, where the neutrino mass is determined via a canonical seesaw, while the dark matter stability is ensured by electric and color charge conservations. We examine the mass spectra of fermions, scalars, and gauge bosons, as well as their interactions, taking into account the kinetic mixing effect of $U(1)_{Y,N}$ gauge fields. The new physics phenomena at colliders are examined. The dark matter relic density and detection are discussed.