district                  vacator                                reason for change                successor date successor seated
0          new jersey 2nd                   vacant  rep t millet hand died during previous congress       milton w glenn (r)     november 5 , 1957
1            illinois 7th         james bowler (d)                              died july 18 , 1957    roland v libonati (d)    december 31 , 1957
2             georgia 7th   henderson l lanham (d)                          died november 10 , 1957    harlan e mitchell (d)      january 8 , 1958
3       pennsylvania 21st   augustine b kelley (d)                          died november 20 , 1957          john h dent (d)     january 21 , 1958
4           tennessee 8th          jere cooper (d)                          died december 18 , 1957  robert fats everett (d)     february 1 , 1958
5         new jersey 14th     vincent j dellay (r)  changed political affiliation some time in 1958     vincent j dellay (d)                  1958
6           illinois 14th     russell w keeney (r)                           died january 11 , 1958                   vacant  not filled this term
7           minnesota 1st    august h andresen (r)                           died january 14 , 1958              al quie (r)    february 18 , 1958
8           wisconsin 1st     lawrence h smith (r)                           died january 22 , 1958                   vacant  not filled this term
9   new mexico at - large       john j dempsey (d)                             died march 11 , 1958                   vacant  not filled this term
10          louisiana 8th        george s long (d)                             died march 22 , 1958                   vacant  not filled this term
11           illinois 4th      william e mcvey (r)                            died august 10 , 1958                   vacant  not filled this term
12      pennsylvania 28th  herman p eberharter (d)                          died september 9 , 1958                   vacant  not filled this term
13          illinois 20th          sid simpson (r)                           died october 26 , 1958                   vacant  not filled this term

Table as JSON:
{"district":{"0":"new jersey 2nd","1":"illinois 7th","2":"georgia 7th","3":"pennsylvania 21st","4":"tennessee 8th","5":"new jersey 14th","6":"illinois 14th","7":"minnesota 1st","8":"wisconsin 1st","9":"new mexico at - large","10":"louisiana 8th","11":"illinois 4th","12":"pennsylvania 28th","13":"illinois 20th"},"vacator":{"0":"vacant","1":"james bowler (d)","2":"henderson l lanham (d)","3":"augustine b kelley (d)","4":"jere cooper (d)","5":"vincent j dellay (r)","6":"russell w keeney (r)","7":"august h andresen (r)","8":"lawrence h smith (r)","9":"john j dempsey (d)","10":"george s long (d)","11":"william e mcvey (r)","12":"herman p eberharter (d)","13":"sid simpson (r)"},"reason for change":{"0":"rep t millet hand died during previous congress","1":"died july 18 , 1957","2":"died november 10 , 1957","3":"died november 20 , 1957","4":"died december 18 , 1957","5":"changed political affiliation some time in 1958","6":"died january 11 , 1958","7":"died january 14 , 1958","8":"died january 22 , 1958","9":"died march 11 , 1958","10":"died march 22 , 1958","11":"died august 10 , 1958","12":"died september 9 , 1958","13":"died october 26 , 1958"},"successor":{"0":"milton w glenn (r)","1":"roland v libonati (d)","2":"harlan e mitchell (d)","3":"john h dent (d)","4":"robert fats everett (d)","5":"vincent j dellay (d)","6":"vacant","7":"al quie (r)","8":"vacant","9":"vacant","10":"vacant","11":"vacant","12":"vacant","13":"vacant"},"date successor seated":{"0":"november 5 , 1957","1":"december 31 , 1957","2":"january 8 , 1958","3":"january 21 , 1958","4":"february 1 , 1958","5":"1958","6":"not filled this term","7":"february 18 , 1958","8":"not filled this term","9":"not filled this term","10":"not filled this term","11":"not filled this term","12":"not filled this term","13":"not filled this term"}}