Winkler was born in Neustadt, Grey County, Canada West, and educated at public schools in the area.
The Liberals were defeated in the 1899 provincial election, although Winkler retained his seat with a victory over Conservative candidate W.J.
Winkler's son later wrote that his father was not keen on entering federal politics, but ran at the behest of Clifford Sifton, a prominent cabinet minister from Manitoba.
Twelve days after the federal election, Winkler was narrowly re-elected in a by-election to serve Rhineland again in the provincial legislature.
The Conservative administration of Rodmond Roblin governed the province throughout this period, and Winkler served as a member of the opposition.
In 1915, Roblin was forced to resign from office after the Lieutenant Governor found his ministry guilty of corruption in the tendering of contracts for new legislative buildings.
Winkler defeated Tupper a second time, and was retained as Agriculture and Immigration minister in Norris's government.