a) When a horse wins the KY Derby, is that horse automatically the favorite for the Preakness, if entered? If not, why not?
b) How did the races that define the Triple Crown come to be narrowed down to those three races? Were others considered? - Jinx
Nobody’s ever “automatically” a favorite – the market sort of makes itself.
Reasons he might not be the favorite in the Preakness:
(1) Circumstances that suggest his win was a fluke (the other favorites all collided, or it is the only race out of 500 he’s run that he won).
(2) Another good horse was not in the KY Derby (heh heh heh I said “KY”), either because of injury, owner caprice, etc.
(3) Different jockey in the Preakness (unusual, I’d guess, but it could certainly change the handicapping).
That said, a Kentucky Derby winner will often attract lots of money (and hence short odds) for the Preakness.
Barbaro is, in fact, currently the favorite, at even odds on Sportsbook.com.
. . . but that other good horse is entered in the Preakness, I should have made clear.
Horse racing is set up as a parimutuel betting system. The odds are determined by the bettors, more money on one horse than any other makes that horse “the favorite”. It isn’t any individuals assessment, just a calculation based on which horses people are betting on.
Correct – good discussion of this and other basics in:
http://boards.straightdope.com/sdmb/showthread.php?t=371798&highlight=parimutuel
There has been a ‘Triple Crown’ in British racing for an unknown number of years (since al least the 1800’s), consisting of the Two Thousand Guineas, the English Derby, and the St. Leger.
The American ‘Triple Crown’ is presumably named after that. The term was used occasionally in the 1920’s and maybe before, but became common when an influential writer on the Daily Racing Form began using it after Gallant Fox won all three races in 1930.
Why these 3 races?
They were the best known, held at famous tracks, and paid some of the highest winnings in American races*.
The term was sometimes used to refer to other races. For example, the Coney Island track had a series of 3 races they called the ‘triple crown’. But such other usages died out, and people hearing ‘triple crown’ today think of these 3 races.
This is no longer true; there are now several races in America that pay more than the Triple Crown races.
It should perhaps be noted that the Triple Crown races were never intended to be the richest or best races period, but the richest and most prestigious races for 3-year-olds–a chance for young horses just entering their racing prime to compete against each other.
Unfortunately, the economics of racing are such that many of the best horses retire to stud and don’t compete when older, so that races such as the Breeders Cup for older horses have never attained the popular cachet of the Triple Crown races.