John Edward Broadbent was a Canadian social-democratic politician and political scientist. He was leader of the New Democratic Party (NDP) from 1975 to 1989, and a member of Parliament from 1968 to 1990 and from 2004 to 2006. He led the NDP through four federal elections. He oversaw a period of growth for the party with its parliamentary representation rising from 17 to 43 seats as of the 1988 federal election.

The New Democratic Party is a federal political party in Canada. Widely described as social democratic, the party occupies the centre-left of the political spectrum, with the party generally sitting to the left of the Liberal Party. The party was founded in 1961 by the Co-operative Commonwealth Federation (CCF) and the Canadian Labour Congress (CLC).