** FILE ** In this Jan. 7, 2014, file photo, New Jersey Gov. Chris Christie sits with students during a gathering at Colin Powell elementary school in heavily Hispanic Union City, N.J. after he ceremonially signed a bill that lowers tuition costs at public colleges for New Jersey students who lack lawful immigration status. A day after revelations that Christie's administration may have closed highway lanes to exact political retribution, the prospective Republican presidential candidate is faced with what may be the biggest test in his political career. (AP Photo/Mel Evans, File)