  Let $M^{2d}$ be a compact symplectic manifold and $T$ a compact
$n$-dimensional torus. A Hamiltonian action, $\tau$, of $T$ on $M$ is a GKM
action if, for every $p \in M^T$, the isotropy representation of $T$ on $T_pM$
has pair-wise linearly independent weights. For such an action the projection
of the set of zero and one-dimensional orbits onto $M/T$ is a regular
$d$-valent graph; and Goresky, Kottwitz and MacPherson have proved that the
equivariant cohomology of $M$ can be computed from the combinatorics of this
graph. (See \cite{GKM:eqcohom}.) In this paper we define a ``GKM action with
non-isolated fixed points'' to be an action, $\tau$, of $T$ on $M$ with the
property that for every connected component, $F$ of $M^T$ and $ p \in F$ the
isotropy representation of $T$ on the normal space to $F$ at $p$ has pair-wise
linearly independent weights. For such an action, we show that all components
of $M^T$ are diffeomorphic and prove an analogue of the theorem above.
