The Kentucky Derby field was enormous, but not every horse that ran that race will continue their trek through the Triple Crown. The Preakness will feature a few horses that we did not see in the Derby, and the term reserved for those pokes is "new-shooters." The "new-shooters" that will be entering the Preakness are Brimstone Island, Cozzetti, Guyana Star Dweej, Hierro, Paynter, Pretension, Teeth of the Dog, Tiger Walk and Zetterholm. You can read a little bit more about each of these horses at SB Nation, but here is some more info on the horse that seems to have the best chance, Teeth of the Dog.
Like Paynter, this colt is lightly raced and still developing, which is potentially a huge combination in any race. He hasn't raced since April 7th and could be ready to fire a big race right off the short layoff.
The last new-shooter to win the Preakness was Bernadini in 2006, so it isn't a very frequent occurrence but it does happen sometimes.
For more on the Preakness Stakes and the race for the Triple Crown, stay with this StoryStream and check out SB Nation's horse racing blog And Down The Stretch They Come. There, you'll also find a A Beginner's Guide To Following Horse Racing and a glossary of horse racing terms.