* Cardinals' Carpenter falters * Giants stave off elimination again (adds details) Oct 21 - The San Francisco Giants fought off elimination from the National League Championship Series yet again on Sunday, beating the visiting St. Louis Cardinals 6-1 to force a deciding Game Seven. Giants starter Ryan Vogelsong delivered seven stellar innings that included a career-high nine strikeouts to help tie the best-of-seven series at 3-3. On Friday, Barry Zito helped keep the Giants' season alive, pitching into the eighth inning of a 5-0 shutout that extended the NLCS to a sixth game. ...