He was educated at the Lawrence Sheriff School in Rugby and later on a scholarship at Rugby School and read History at Sidney Sussex College, Cambridge University, gaining a first-class Honours degree. He was a member of Cambridge University Social Democrats. He was also editor of Stop Press the Cambridge University newspaper of the day, and won the Guardian Student Journalist of the year award in 1984.
Rawnsley began his career at the BBC, working there for two years from 1983, but joined The Guardian in 1985. From 1987 he was the newspaper's parliamentary sketch writer.
In 1993 he moved to The Observer as Chief Political Commentator and Associate Editor, a position he retains. He has won several awards for his journalism, including: British Press Awards Young Journalist of the Year (1987); What The Papers Say Columnist of the Year (2000); Channel 4 Political Awards Book of the Year (2001); Channel 4 Political Awards Journalist of the Year (2003); House Magazine Awards Commentator of the Year (2008).
Radio and television
Rawnsley has also broadcast regularly; he was co-presenter of Channel 4's A Week in Politics with Vincent Hanna. He continues to be the writer-presenter of one-off documentaries for Channel 4. He made Bye Bye Blues, a three part series about John Major's Government, in 1997. That was followed by Blair's Year (1998). His three hour series The Rise And Fall Of Tony Blair (2007) was long-listed for a BAFTA award. This was followed by Gordon Brown: Where Did It All Go Wrong? (2008), which was nominated for a BANFF award, and Crash Gordon: The Inside Story of the Financial Crisis (2009).
He was the founding and sole presenter of BBC Radio Four's The Westminster Hour from 1998 to September 2006. He was succeeded by Carolyn Quinn when he moved to the ITV network for a new programme, The Sunday Edition, with Andrea Catherwood, a series which began on Sunday 17 September 2006.
Rawnsley's Servants of the People (2000, paperback revision 2001) is an account of the early years of New Labour in government. In particular the book raised the profile of the feud between Tony Blair and Gordon Brown.
Rawnsley's The End of the Party was published on 1 March 2010. On 31 January 2010, the Mail on Sunday reported that the new book will make allegations that the prime minister, Gordon Brown, physically attacked members of his staff. The book was a number one bestseller in its first week of publication.