  We study N=2 supersymmetric gauge theories on squashed 3-sphere and S^1xS^2.
Recent studies have shown that the partition functions in a class of N=2
theories have factorized forms in terms of vortex and anti-vortex partition
functions by explicitly evaluating matrix integrals obtained from Coulomb
branch localization. We directly derive this structure by performing Higgs
branch localization. It turns out that more general N=2 theories have this
factorization property. We also discuss the factorization of supersymmetric
Wilson loop.
