Born in Australia, Ramsay moved to Canada with his parents at age one after having been adopted in Sydney, and was raised in Oakville, Ontario. He attended Concordia University in Montreal, and after graduation worked as a farmer in New Liskeard and a clerk-treasurer in Casey Township, in northern Ontario. He later served as president of the Timiskaming Federation of Agriculture in 1984-85, was a founding member of the Timiskaming Grain Growers Board, and served as chair of the Timiskaming Hospital Board for a time. Ramsay died on July 29, 2020 at the age of 72.
In the 1985 provincial election he ran as the New Democrat candidate in the northern Ontario riding of Timiskaming. He defeated Progressive Conservative incumbent Ed Havrot by almost 3000 votes, as the once-powerful Tory machine in northern Ontario began to lose its support base. He served as a critic of Small Business, Financial Institutions, and Agriculture and Food.
On 6 October 1986, Ramsay crossed the floor to join the governing Liberals, claiming that Northern Ontario needed greater representation in government. Despite an intense effort by the NDP to defeat Ramsay in the 1987 election, he won re-election by over 4,000 votes. On 29 September 1987, Ramsay was appointed to David Peterson's cabinet as Minister of Correctional Services. Following a cabinet shuffle on 2 August 1989, he was named Minister of Agriculture and Food. Ramsay kept his seat in the 1990 election that defeated the Liberal government and brought Ramsay's former party, the NDP, to power under Bob Rae. He ran for the leadership of the Liberal Party in the 1992 Liberal leadership convention, but placed last in a field of six candidates. Like fellow candidate Greg Sorbara, his campaign included both right-wing and left-wing elements. He supported tax reduction, and favoured open Sunday shopping and allowing corner stores to sell beer and wine. He also supported pay equity measures, and described himself as pro-choice on abortion. In the provincial elections of 1995 and 1999, Ramsay's primary opposition came not from the New Democrats but the Progressive Conservatives, whose leader Mike Harris represented a neighbouring riding. He won by a clear margin on both occasions. In 1996, he endorsed Dwight Duncan's bid to lead the Ontario Liberal Party. Ramsay served as caucus chair from 1993 to 1994 and again from 1999 to 2003. With the victory of the Liberals under the leadership of Dalton McGuinty in the 2003 election, Ramsay returned to cabinet as Minister of Natural Resources on 23 October 2003. He was also given responsibility for Aboriginal Affairs on 29 June 2005. In June 2007, Ramsay was appointed Ontario's first Minister of Aboriginal Affairs. In the 2007 provincial election, Ramsay won by 634 votes over NDP candidate John Vanthof. Ramsay expected to continue as a minister but was dropped from cabinet. Instead he was appointed as McGuinty's Parliamentary Assistant. In January 2011 he said that he was retiring from politics and would not run in the 2011 election.