A method and apparatus for closing a vascular wound includes an apparatus that can be threaded over a guidewire into place at or adjacent the wound. The apparatus includes a chamber that encloses a hemostatic material therein. When the apparatus is positioned adjacent the wound as desired, the hemostatic material is deployed from the chamber. Blood contacts the hemostatic material, and blood clotting preferably is facilitated by a hemostatic agent within the material. Thus, the vascular puncture wound is sealed by blood clot formation.