  New defects (Z-vortices and Nambu monopoles) are found to become
thermodynamically relevant for the broken phase near to the (weakly first
order) electroweak phase transition, and below the crossover for higher Higgs
mass. The symmetric phase is characterized by vortex condensation
(percolation). The percolation transition persists in the crossover region. The
quasiclassical nature of the vortices is supported by correlations with Higgs
field and gauge field energy. Sphalerons are shown to be related to monopolium
bound states.
