Before I called Bernie Sanders, I lit a candle in my living room and put on some gospel music. I wanted to center myself for what I knew would be an emotional phone call.

I had promised Bernie when I took the helm of the Democratic National Committee after the convention that I would get to the bottom of whether Hillary Clinton's team had rigged the nomination process, as a cache of emails stolen by Russian hackers and posted online had suggested. I'd had my suspicions from the moment I walked in the door of the DNC a month or so earlier, based on the leaked emails. But who knew if some of them might have been forged? I needed to have solid proof, and so did Bernie.So I followed the money. My predecessor, Florida Rep. Debbie Wasserman Schultz, had not been the most active chair in fundraising at a time when President Barack Obama's neglect had left the party in significant debt.