We explore a new possibility of electroweak baryogenesis in the
next-to-minimal supersymmetric standard model. In this model, a strong
first-order electroweak phase transition can be achieved due to the additional
singlet Higgs field. The new impact of its superpartner (singlino) on the
baryon asymmetry is investigated by employing the closed-time-path formalism.
We find that the CP violating source term fueled by the singlino could be large
enough to generate the observed baryon asymmetry of the Universe without any
conflicts with the current constraints from the non-observation of the
Thallium, neutron and Mercury electric dipole moments.Comment: 11 pages, 2 figures. To appear in PL