Since Confederation, North Grenville has elected Conservative Party members, almost exclusively, at both the federal and provincial levels, for all but 19 years in Ottawa, and all but four years in Toronto. There was a short period in 1874 when sitting Conservative member, Francis Jones, crossed the floor to join the Liberals. However, he was ousted by voters at the next election in 1878.
The only Liberal elected to the provincial legislature was Henry Dolphus Smith, who served from 1867 until 1871. It should be noted that, during that period, there was a coalition government between Liberals and Conservatives at the provincial level. By 1871, the Ontario Liberals began a very long period in government in Toronto. Even so, this riding continued to be represented by Conservatives throughout that time.