 So how he does tonight could go a long way toward easing some of those concerns and maybe bringing some of those undecided voters onto his side. Now to President Trump, he didn't take part in any of the GOP primary debates. It's been a while since he's been on a debate stage. Trump saying that he would debate Biden anytime, anywhere. That time is tonight. Watching how he's been preparing, ABC News national correspondent Stephen Portnoy. Hi, Stephen.