  We analyze the moduli space of the low-energy limit of 3-dimensional N=3
Maxwell-Chern-Simons theories described by circular quiver diagrams, as for
4-dimensional elliptic models. We define the theories by using
D3-NS5-(k,1)5-brane systems with an arbitrary number of fivebranes. The
supersymmetry is expected to be enhanced to N=4 in the low-energy limit. We
show that the Higgs branch, in which all bifundamental scalar fields develop
vacuum expectation values, is an abelian orbifold of C^4. We confirm that the
same geometry is obtained as an M-theory dual of the brane system. We also
consider theories realized by introducing more than two kinds of fivebranes,
and obtain nontoric fourfolds as moduli spaces.
