Denman was appointed to the Senate in August 1993 to fill a casual vacancy caused by the resignation of Senator
Michael Tate. She was Deputy Government Whip in the Senate from 1995 to 1996 and Deputy Opposition Whip in the Senate from 1997 to 2001. Denman was a long-running chair of the Senate Standing Committee on Senators' Interests between 1996 and 2005. She was re-elected in her own right at the
1998 election and retired at the
2004 election. Her term expired on 30 June 2005. She had a strong interest in health, education and access issues during her time in parliament, and was an advocate for people with disabilities,
asbestos-related issues (her hometown of Railton had a major asbestos factory) and gay and lesbian rights. ==Later career==