  The magnetic susceptibility and spin-spin correlation of the double-exchange
model for doped manganites are investigated through the Monte Carlo
calculations on the three-dimensional lattice model. Deviations of the
susceptibility from the Curie-Weiss behavior above the ferromagnetic ordering
temperature $T_c$ seem to indicate a formation of local ferromagnetic clusters
in the vicinity of $T_c$, which is consistent with recent electron paramagnetic
resonance experiments for La$_{2/3}$Ca$_{1/3}$MnO$_3$. A further analysis of
the spin-spin correlations show the ferromagnetic cluster size to be
three-to-four lattice spacings, suggesting that the charge carriers may form
magnetic polarons.
