A potential upgrade of the SuperKEKB e$^+$e$^-$ collider with a polarized electron beam
will open a new program of precision electroweak physics at the centre-of-mass energy of the $\Upsilon$(4S) and is currently being considered.
These measurements include $\sin^2\theta_W$ obtained via left-right asymmetry measurements of
e$^+$e$^-$ transitions to pairs of electrons, muons, taus, charm and b-quarks.
The precision obtainable at SuperKEKB will match that of the LEP/SLC world average but at the centre-of-mass energy of 10.58~GeV,
thereby probing the neutral current couplings with unprecedented precision at a new energy scale sensitive to the running of the couplings.
World average measurements of the individual neutral current vector coupling constants to b- and c-quarks and muons in particular will be
substantially improved and the residual $3\sigma$ discrepancy between the SLC $A_{LR}$ and LEP $A_{FB}^b$
measurements will be addressed. This paper will include a discussion of the necessary upgrades to SuperKEKB.
This program opens an exciting new window in searches for physics beyond the standard model