LBJ'S 3/6/68 MEETING WITH FULBRIGHT, MANSFIELD, HICKENLOOPER, AIKEN, SPARKMAN; SENATE DEBATE ON VIETNAM YESTERDAY; LBJ'S TALK WITH RICHARD RUSSELL; AUGUST 1964 TONKIN GULF ATTACKS; NEED FOR MORE TROOPS; DOD BUDGET; NEW HAMPSHIRE PRIMARY; RESERVE CALL-UP