  We quantize the spontaneously broken abelian U(1) Higgs model by using the
improved BFT and BFV formalisms. We have constructed the BFT physical fields,
and obtain the first class observables including the Hamiltonian in terms of
these fields. We have also explicitly shown that there are exact form
invariances between the second class and first class quantities. Then,
according to the BFV formalism, we have derived the corresponding Lagrangian
having U(1) gauge symmetry. We also discuss at the classical level how one
easily gets the first class Lagrangian from the symmetry-broken second class
Lagrangian.
