President George W. Bush visited the CME in early 2001 and walked into the S&P 500 pit during the last hour of trading as pictured above. I didn't go down to see him but should've in retrospect because I've really come to admire and appreciate him. After the market closed Bush gave a short speech on allowing Americans to keep more of what they earn through tax cuts to what was obviously a receptive audience.
His full remarks are linked here:
Remarks by the President at Chicago Mercantile Exchange