  We derive an Abelian-Higgs-like action from SU(2) Yang-Mills theory via
monopole-condensation assumption. Abelian projection as well as
chromo-'electric-magnetic' duality are naturally realized by separating the
small off-diagonal gluon part from diagonal gluon field according to the order
of inverse coupling constant($1/g$). It is shown that Abelian dominance can
follow from infrared behavior of ranning coupling constant and the mass
generation of chromo-electric field as well as off-diagonal gluon is due to the
quantum fluctuation of orientation of Abelian direction. Dual superconductivity
of theory vacuum is confirmed by deriving dual London equation for
chromo-electronic field.
