|South Dakota State Senate District 9|
| Term in office began|
| Term in office ended|
Prior to leaving the senate, Dempster served as Assistant Majority Leader.
Dempster works as a financial advisor. Dempster earned his BA in Economics from the University of South Dakota. Dempster was a member and president of the South Dakota County Commissioners from 1989 to 1998.
Prior to leaving the South Dakota State Senate, Dempster served on the following committees:
- Health and Human Services Committee, South Dakota Senate
- State Affairs Committee, South Dakota Senate
Dempster is not eligible to run for re-election to the 9th District Seat in 2010 due to South Dakota's term limits. The general election took place on November 2, 2010.
Dempster raised $55,487 for his campaign while Nielson raised $0. 
|South Dakota State Senate, District 9 (2008)|
|Tom Dempster (I)||5,109||52.30%|
|Paul Nielson (D)||4,660||47.70%|
Dempster raised $55,487 during the 2008 election cycle.
His top contributors are listed below.
|South Dakota Republican Party||$5,656|
|All South Dakota PAC||$3,000|
|South Dakota Growers Association||$1,500|
|South Dakota Association of Specialty Care Providers||$1,250|
|A Better South Dakota PAC||$1,000|
|South Dakota Beer Wholesalers Association||$1,000|
Dempster and his wife Patti have three children.
|South Dakota Senate District 9
| Succeeded by|
Deb Peters (R)