state (class)                   vacator                     reason for change                  successor date of successor 's formal installation
0    georgia (2)  richard russell , jr (d)                died january 21 , 1971       david h gambrell (d)                        february 1 , 1971
1    vermont (1)      winston l prouty (r)              died september 10 , 1971        robert stafford (r)                      september 16 , 1971
2  louisiana (2)      allen j ellender (d)                   died july 27 , 1972       elaine s edwards (d)                          august 1 , 1972
3    georgia (2)      david h gambrell (d)   successor elected november 7 , 1972               sam nunn (d)                        november 7 , 1972
4  louisiana (2)      elaine s edwards (d)  successor elected november 13 , 1972  bennett johnston , jr (d)                       november 14 , 1972

Table as JSON:
{"state (class)":{"0":"georgia (2)","1":"vermont (1)","2":"louisiana (2)","3":"georgia (2)","4":"louisiana (2)"},"vacator":{"0":"richard russell , jr (d)","1":"winston l prouty (r)","2":"allen j ellender (d)","3":"david h gambrell (d)","4":"elaine s edwards (d)"},"reason for change":{"0":"died january 21 , 1971","1":"died september 10 , 1971","2":"died july 27 , 1972","3":"successor elected november 7 , 1972","4":"successor elected november 13 , 1972"},"successor":{"0":"david h gambrell (d)","1":"robert stafford (r)","2":"elaine s edwards (d)","3":"sam nunn (d)","4":"bennett johnston , jr (d)"},"date of successor 's formal installation":{"0":"february 1 , 1971","1":"september 16 , 1971","2":"august 1 , 1972","3":"november 7 , 1972","4":"november 14 , 1972"}}