Rules differ slightly, but names pretty much are the same, at least at the top. Jarhead, who has been running roughshod over the Las Vegas Hilton SuperContest field, also is knocking 'em dead in two other Sin City high-end football contests, which, not coincidentally, were germinated by former SuperBook bosses. Jarhead, a nickname for members of the United States Marines, takes a comfy 3 1/2 cushion into the final four weeks of the Hilton competition.