In this April 2, 1968, file photo Sen. Robert F. Kennedy, D-NY, shakes hands with people in a crowd while campaigning for the Democratic party's presidential nomination  in  Philadelphia.  The author has a copy of this photo in his office.
In this April 2, 1968, file photo Sen. Robert F. Kennedy, D-NY, shakes hands with people in a crowd while campaigning for the Democratic party's presidential nomination in Philadelphia. The author has a copy of this photo in his office. Warren Winterbottom Associated Press
In this April 2, 1968, file photo Sen. Robert F. Kennedy, D-NY, shakes hands with people in a crowd while campaigning for the Democratic party's presidential nomination in Philadelphia. The author has a copy of this photo in his office. Warren Winterbottom Associated Press