Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| District | Incumbent | Party | First elected | Result | Candidates |
| --- | --- | --- | --- | --- | --- |
| Tennessee 2 | John Jennings | Republican | 1939.0 | Re-elected | John Jennings (R) 56.6% Clay James (D) 43.4% |
| Tennessee 3 | Estes Kefauver | Democratic | 1939.0 | Re-elected | Estes Kefauver (D) 68.7% Jerome Taylor (R) 31.3% |
| Tennessee 4 | Albert Gore, Sr. | Democratic | 1938.0 | Re-elected | Albert Gore, Sr. (D) 88.9% H. E. McLean (R) 11.1% |
| Tennessee 6 | W. Wirt Courtney | Democratic | 1939.0 | Re-elected | W. Wirt Courtney (D) Unopposed |
| Tennessee 7 | Herron C. Pearson | Democratic | 1934.0 | Re-elected | Herron C. Pearson (D) Unopposed |
Question:
What is the latest year any of the incumbents were first elected? 
Answer:
1939.0