We present a realization of the dual superconductor hypothesis of confinement in SU(2) gauge theory. We construct an approximate effective action for a class of t'Hooft-Polyakov-like monopole configurations in pure SU(2) gauge theory which can be mapped to periodic QED. The key point in this mapping is that the renormalized coupling in the effective action is mapped onto the bare coupling in the periodic U(1) theory. A variational calculation leads to the estimate square-root-sigma almost-equal-to 2.2-LAMBDA-R = 2.3-LAMBDA-MSBAR for the string tension.