Johnston ran in the 1982 NDP leadership convention to succeed Michael Cassidy. He characterized himself as a 'rank-and-file' candidate who was more in tune with the grassroots of the party in contrast with Bob Rae who had the support of leaders in the party and the trade union movement. Johnston received support from the left wing of the party including MPPs Floyd Laughren, Jim Renwick and Ross McClellan. Johnston promoted a strong anti-nuclear stand and was proponent of nationalizing key industries such as the banks, Bell Canada and natural resource companies such as Inco's mining and smelting operations. On February 7, 1982, Rae won on the first ballot with 64.5% of the vote beating Johnston by 844 votes. Johnston was magnanimous in defeat saying of Rae, "a leader with an unparalleled capacity to turn a phrase and turn on a crowd. I will be proud to serve in the Legislature with Bob Rae as my leader."