Victory! For betting purposes the 1-2-3 placed horses is called win-place-show in that order.
The rider of a horse in a race is called a Jockey.
an also-ran refers to losing horses in a horse race
The farthest distance a race horse has come from behind to win is great. This horse went from last place to first place.
A steward.
A person who rides horses (mainly thoroughbreds) is called a Jockey
Not that I've heard of.
A horse jockey's mount is called a horse. The mount refers to the horse that the jockey rides during a race or competition.
yes
This is the show horse. Win, place and show.
The common sobriquet for Thoroughbred horse racing is called The Sport of Kings.
A stallion like the rest
Horse blinders are used on race tracks so the horse can't be distracted. In Canada they may also be called blinkers.