The same shot is used repeatedly during the race. The crowd is shown with the same clip twice and the horses at the 1/4 mile point and with 1/4 mile to go are from the same clip (cropped differently) and used once again later.
A man on the ground behind the second to last horse on the right is seen whipping the horse just as the gates open. That horse runs to the lead & is assumed to be #5 (Ronnie Watson's horse).