Yeah, you can use 100% silicone caulking for repairs, but use a piece of pantyhose fabric for backing on the inside. Make sure the tear edges are clean and dry, then spread it inside the crack, as much as you can on the outside to match, then a good bit beyond the nylon on the inside. Not too thick of a coat, then let dry according to directions before wear.
We've been using that new extra stretch silicone caulk.
Oh yeah - One more thing - always make sure you check the expiration date on caulk!! it does have a shelf life and lots of times you'll find stores selling the expired stuff.