Democratic debate live chat: An energetic exchange breaks out among the candidates in Miami

Hi folks! Looking forward to the first Democratic debate tonight. Joe Biden and Bernie Sanders — the two front-runners — won’t be on the stage until tomorrow night. I am wondering how much of a boost their absence gives Elizabeth Warren, whose campaign already appears to be surging. The rest of the candidates on the stage tonight are polling in the single digits, at best. Will one of them, say Beto O’Rourke or Cory Booker or Amy Klobuchar, have a breakthrough moment tonight? If so, is it because they break through with a compelling message about why they are running for president, or because they attack the front-runners?