Sanders chooses Clinton over Canova

In the clip below The Humanist Report (HR) criticized Sanders for abandoning Canova's bid to usurp the Democratic nomination from Wasserman-Schultz (WS) in FL. Sanders was asked about it on Meet the Press and dodged the question completely. HR wonders why Sanders chose instead to campaign for the establishment Dem Clinton and abandon the Canova challenge, since the latter was a key race that represented the exact values and policies Sanders espoused. And WS was exactly the type of corporate Dem that Sanders campaign has been fighting against all along. So WTF gives Sanders?