Ontario CCF/NDP leadership elections

(Held on April 3, 1942, at the Hotel Carls-Rite in Toronto)^[1]

• Ted Jolliffe
• Murray Cotterill

Fifteen other individuals were nominated but declined to stand including Ontario CCF President and former Hamilton East MPP Samuel Lawrence; Allan Schroeder of St. Catharines; York West Member of Parliament Joseph W. Noseworthy; Canadian United Steelworkers of America executive director Charles Millard, lawyer Andrew Brewin; former Member of Parliament Agnes MacPhail; Toronto alderman William Dennison, CCF National Secretary David Lewis; University of Toronto professor and Toronto school trustee George Grube; teacher Everett Orlan Hall of London, Ontario; Alderman and former party president John Mitchell of Hamilton; B.E. Leavens of Toronto; Lou Isaacs; William Grant of Peterborough, and Margaret Sedgewick of Toronto.^[1][2]

(Note: The vote totals were not announced. 150 delegates participated in total.^[1])

(Held November 23, 1946)

• Ted Jolliffe
• Lewis Duncan

(Held at the Royal Canadian Legion Hall on College Street, in Toronto, on November 21, 1953.)^[3]

Former MPPs Agnes Macphail, Eamon Park, Charles Millard, and William Dennison were nominated as was sitting MPP and CCF house leader Bill Grummett but all declined.^[4]

(Note: These totals are taken from an interview with Donald C. MacDonald several years after the convention. They do not appear to have been announced at the convention itself.)

(Held on October 8, 1961, at the Sheraton-Brock Hotel in Niagara Falls, Ontario)^[5]

• Donald C. MacDonald acclaimed

(Held on November 17, 1968, at Bingeman Park in Kitchener, Ontario.)^[6]

(Held at the Royal York Hotel in Toronto on October 4, 1970.)^[7]

(Held on December 10, 1972, at the Four Seasons Sheraton Hotel in Toronto, Ontario.)^[8]

An additional 137 ballots were spoiled. If the spoiled votes are factored in then Lewis received 74.2% support overall

(Held on February 5, 1978, at the Sheraton Centre in Toronto.)^[9]

Breaugh eliminated, goes to Cassidy

(Held at the Harbour Castle Convention Centre in Toronto on February 7, 1982.)^[10]

(Held on June 22, 1986, at Copps Coliseum in Hamilton, Ontario.)

(Held on June 22, 1996, at Copps Coliseum in Hamilton, Ontario.)

After the first ballot, Silipo was eliminated and he endorsed Hampton. After the 2nd ballot, Kormos was eliminated but he endorsed no one and released his delegates. There were eighty spoiled ballots on the final count, mostly from disgruntled supporters of Kormos.

(Held on March 7, 2009, at Copps Coliseum in Hamilton, Ontario)

Prue eliminated, endorses Bisson

Bisson eliminated, endorses Horwath

Starting with the 2009 leadership election, the Ontario NDP instituted a modified one member one vote system in which the vote is calculated so that ballots cast by labour delegates have 25% weight in the total result, while votes cast by party members have a weight of 75% in the overall result.

(Held on February 4, 2023, at the Metro Toronto Convention Centre in downtown Toronto)

• Marit Stiles acclaimed^[11]