  We report electronic transport measurements of graphene contacted by NbTiN
electrodes, which at low temperature remain superconducting up to at least 11
Tesla. In devices with a single superconducting contact, we find a more than
twofold enhancement of the conductance at zero bias, which we interpret in
terms of reflectionless tunneling. In devices with two superconducting
contacts, we observe the Josephson effect, bipolar supercurrents and Fraunhofer
patterns.
