I do think Bush is smart, yes. Misspeaking, espacially public speaking, in my mind, is not evidence of a lack of intelligence. I think it is 'stupid' to assume so.
Do I think he's brilliant? Probably not, no. But I don't think he is dim, if that is what you are asking. He has good judgment, IMO. That is a form of intelligence, one that is more important than "book smarts" in my opinion. I think Bush is HIGHLY street-smart, for lack of a better phrase. Bush "gets it." he sees things how they actually are and is decisive and confident in himself. That confidence has usually translated into success, especially in his brief political career.
I think Bill Clinton is smarter, sure. I think Bill Clinton is a brilliant man, actually. He's smarter than most people, I would imagine.
I also think Dan Quayle was smart and that Ronald Reagan was smart. The "conservatives as dumb" line is a tired cliche, IMO. Dan Quayle was obviously not dumb, but that didn't stop the attacks, initially because of his youthful appearance. The "Quayle as idiot" perception was out there long before "P-O-T-A-T-O-E" and that simple spelling mistakes was blown so far out of proportion as to be ludicrous, especially since there IS an E in the plural form of that noun. Dean thinks there is still a "Soviet Union" but do you hear any 'Dean is dumb" remarks? Al Gore got "E pluribus Unum" reversed and got horroble grades and failed out of a shool, but was he "dumb?"
I also think Bush is an honest, decent and sincere man. I think Al Gore is a decent man, even honest in his way. It's impossible for a professional politician to seem 100% sincere. They almost HAVE to contradict earlier statements, it's almost impossible not to. But I do think Gore is a decent person and wasn't revolted by him the way others were.