VOX
Bernie needs to prove he's not dead.
Biden needs to fight for his life.
These are the two most closely watched elements of tonight's debate.
Here are my predictions:
Tulsi Goes Full Network - The Hawaii Rep. teased that she was not going to show up to the debate. She'll be on the stage but likely (based on poll numbers) for the last time so what does she have to lose? My guess is that she takes time to rip the debate structure and accuse the DNC of rigging another primary. Watch for her to make the most the time by telling people to go to their windows, open them, and yell "I'm mad as hell and I'm not going to take it anymore!"
Yang Gets A China Question And Makes It Awkward - Since Yang has played the debate qualification game as well as anyone could, he can't bitch about the system too much. But he CAN point out (as he has on Twitter) that the son of Taiwanese immigrants has answered a question about China in each debate. For someone that's only gotten a handful of direct questions, that's a much higher percentage than other candidates. It will be an awkward viral way to point out how little screen time he's gotten.
Bernie Goes After Biden - I've previously feel victim to believe the pre-debate hype about who is going to attack who. Before Houston, Biden's team leaked that he'd trash Warren. He didn't, he picked on Bernie. Now Bernie has drawn a line between himself and Warren... so I am predicting that he will go after Biden.
There are a two advantages to this. First, it shows Bernie has fight in him, a key checkmark for the optics. Second, he's the only candidate older than Joe, so no one can accuse him of piling on the elder statesman.