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:
| Poll Source | Dates administered | Democrat: Dick Durbin | Republican: Steve Sauerberg | Lead Margin |
| --- | --- | --- | --- | --- |
| Rasmussen Reports | October 13, 2008 | 62% | 31% | 31.0 |
| St. Louis Post Dispatch/ Research 2000 | September 15-September 18, 2008 | 56% | 35% | 21.0 |
| Rasmussen Reports | September 17, 2008 | 59% | 35% | 24.0 |
| Rasmussen Reports | August 12, 2008 | 61% | 33% | 28.0 |
| Southern Outreach | July 12, 2008 | 52% | 35% | 17.0 |
Question:
Name the republican steve sauerberg where dates administered september 15-september 18, 2008
Answer:
35%