His refusing to say he would concede if he lost the election should disqualify him, but so should so many other things he's said, and done. It may turn off those already turned off by him but it won't change his supporters.
She had more facts and reality based answers, and I know to her supporters, among which I classify myself, she won handily, but anyone still undecided is someone who hasn't gotten all the facts and/or doesn't believe them and wants to be convinced emotionally.
I wish she, and Democrats in general, slammed back at rightwing distortions with strong empathic clear and simple statements of passion repetitively as they do. Hilary started to do that a few times, like when she said he choked when he met with the Mexican president. But then she let him get away with soft pedaling that and getting emotionally emphatic about how he'd make great deals with Mexico and her deals did and will suck etc.
It's being declared a victory for her and will probably keep her well in the lead, but my guess is he might pick up a few points because she often sounded like she was reciting speech excerpts or policy points rather than expressing spontaneous passion. Hope I'm wrong.