  Using Keldysh nonequilibrium Green's function method we study the
spin-dependent transport through impurity-doped few layer graphene sandwiched
between two magnetic leads with an arbitrary mutual orientations of the
magnetizations. We find for parallel electrodes magnetizations that the
differential conductance possesses two resonant peaks as the applied bias
increases. These peaks are traced back to a buildup of a magnetic moment on the
impurity due to the electrodes spin polarization. For a large mutual angle of
the electrodes magnetization directions, the two resonant peaks approach each
others and merge into a single peak for antiparallel orientation of the
electrodes magnetizations. We point out that the tunneling magnetoresistance
(TMR) may change sign for relatively small changes in the values of the
polarization parameters. Furthermore, we inspect the behaviour of the
differential conductance and TMR upon varying the temperature.
