United States Senate elections, 2010 Senate composition at the beginning of the Senate composition at the beginning of the

| D_39_ | D_40_ | D_41_ | D_42_ | D_43_ | D_44_ | D_45_ | D_46_ | D_47_ | D_48_ |
|---|---|---|---|---|---|---|---|---|---|
| R 20 | R 19 | R 18 | R 17 | R 16 | R 15 | R 14 | R 13 | R 12 | R 11 |
| R 1 | R 2 | R 3 | R 4 | R 5 | R 6 | R 7 | R 8 | R 9 | R 10 |