Transverse momentum resummation at smallxfor the Fermilab Tevatron and CERN LHC

Analysis of semi-inclusive hadroproduction in deep inelastic scattering suggests broadening of transverse momentum distributions at $x$ below a few ${10}^{-3}$, which can be modeled in the Collins-Soper-Sterman formalism by a modification of impact-parameter-dependent parton densities. We discuss the consequences of such a modification for the production of electroweak bosons at hadron-hadron colliders. If substantial small-$x$ broadening is observed in forward $Z^0$ boson production in the Tevatron Run-2, it will strongly affect predicted $q_T$ distributions for $W^{\pm }$, $Z^0$, and Higgs boson production at the Large Hadron Collider.