  Critical exponents at the ferromagnetic transition were measured for the
first time in an organic ferromagnetic material tetrakis(dimethylamino)ethylene
fullerene[60] (TDAE-C$_{60}$). From a complete magnetization-temperature-field
data set near $T_{c}=16.1\pm 0.05,$ we determine the susceptibility and
magnetization critical exponents $\gamma =1.22\pm 0.02$ and $\beta =0.75 \pm
0.03$ respectively, and the field vs. magnetization exponent at $T_{c}$ of
$\delta =2.28\pm 0.14$. Hyperscaling is found to be violated by $\Omega \equiv
d^{\prime}-d \approx -1/4$, suggesting that the onset of ferromagnetism can be
related to percolation of a particular contact configuration of C$_{60}$
molecular orientations.
