  Recently proposed new gauge invariant formulation of the Chern-Simons gauge
theory is considered in detail. This formulation is consistent with the gauge
fixed formulation. Furthermore it is found that the canonical (Noether)
Poincar\'e generators are not gauge invariant even on the constraints surface
and do not satisfy the Poincar\'e algebra contrast to usual case. It is the
improved generators, constructed from the symmetric energy-momentum tensor,
which are (manifestly) gauge invariant and obey the quantum as well as
classical Poincar\'e algebra. The physical states are constructed and it is
found in the Schr\"odinger picture that unusual gauge invariant longitudinal
mode of the gauge field is crucial for constructing the physical wavefunctional
which is genuine to (pure) Chern-Simons theory. In matching to the gauge fixed
formulation, we consider three typical gauges, Coulomb, axial and Weyl gauges
as explicit examples. Furthermore, recent several confusions about the effect
of Dirac's dressing function and the gauge fixings are clarified. The analysis
according to old gauge independent formulation a' la Dirac is summarized in an
appendix.
