The picture with 20 or so people in it (with JFK in the center of the back row) is not a picture of his crew. Those are his fellow Swift boat skippers, all officers. Swift boats had a crew of, I think, 5 enlisted men and 1 officer.
Out of the entire group, there is only one of his fellow officers who supports him. Several of the men in the picture are deceased. Several others have declined to express an opinion. The remaining ones (11 or 12, I'm not sure of the exact count) have stated publicly that kerry is 'unfit for command'.