  We consider topological closed string theories on Calabi-Yau manifolds which
compute superpotential terms in the corresponding compactified type II
effective action. In particular, near certain singularities we compare the
partition function of this topological theory (the Kodaira-Spencer theory) to
$SU(\infty)$ Chern-Simons theory on the vanishing 3-cycle. We find agreement
between these theories, which we check explicitly for the case of shrinking
$S^3$ and Lens spaces, at the perturbative level. Moreover, the gauge theory
has non-perturbative contributions which have a natural interpretation in the
Type IIB picture. We provide a heuristic explanation for this agreement as well
as suggest further equivalences in other topological gravity/gauge systems.
