The effective action describing the long range fluctuations in the high temperature phase of the electroweak standard theory is a strongly coupled SU(2)-Higgs model in three dimensions. We outline in detail a model in which the spatial correlation scales in this phase are calculated as inverse relativistic bound-state masses. Selection rules for these states are derived. The correlation masses are calculated by evaluating the bound-state Green function. The scalar-scalar potential and its influence on the masses is investigated. The predictions for the correlation masses agree very well with the lattice data available now.