Probably not many of us. However, anyone with even a hint of a survival instinct could organize a group of folks to distract him (yelling, running, to get his attention on them) and then another group to spring when he's likely to have less chance of shooting (while reloading, or watching the others, or switching between weapons, as he apparently did here). There would certainly be casualties, but they would more than likely be lower.
Any guy who can do that is more than a hero - he’s a true leader of men. I’d vote for him for president no matter what party he ran under...