clark was elected to the manitoba legislature in a by-election called in the mountain constituency after the resignation of high-profile cabinet minister ivan schultz. he defeated progressive conservative marcel boulic by 276 votes, and served for the next three years as a backbench supporter of douglas campbell's government. many liberal-progressives were concerned with clark's relatively narrow margin of victory, as mountain had previously been considered as one of the party's safest seats. clark received support from the constituency's anglo-saxon majority and large flemish population, while boulic did well among french canadians, who made up one third of the electorate.