She was re-elected in the 2004 federal election by over 2,000 votes in a rematch against Gruending. She is the former official opposition critic of Family Issues, Children and Youth, Human Resources Development, the Deputy Prime Minister, Social Economy, Western Economic Diversification, Public Health and Social Development, where she was instrumental in developing the party's child care policies.
In 2006, she was re-elected again, defeating NDP candidate Nettie Wiebe by 6.3 percentage points. She was appointed to the federal cabinet on February 6, 2006, by the new prime ministerStephen Harper, making her the first ever female Canadian federal cabinet minister from the province of Saskatchewan. On May 28, 2007, she announced a new Taxpayers' Bill of Rights and the creation of a Taxpayer's Ombudsman at the Canada Revenue Agency.