Senator Bernie Sanders leads the delegate race after a win in the Nevada caucuses. MSNBC’s Ari Melber reports on how Sanders has taken “the widest victory margin of any race thus far” and how people can debate "polls" and rhetoric about the "frontrunner" but “measurable delegate count is what matters to winning.” This report also features historical context from previous elections, showing how candidates from both parties went on to win the nomination after leading the delegate count heading into Super Tuesday.