Bubba's groping the inner thigh of this stewardess and she appears to be using her hand to keep his wandering fingers from going to high (she also appears to be occupied talking on the intercomm):
It wasn't just "first grope's free", it's lay back, take it, and then if you got problems, put some ice on it...
Look at the way the man on the right looks into the camera after seeing where Clinton's hand is. It's like he's thinking, "Uh oh...was that caught on tape?"