 Even the younger ministers, such as future Prime Minister John Thompson, who sometimes differed with Macdonald on policy, admitted the Prime Minister was an essential electoral asset for the Conservatives.Blake, whom Macdonald biographer Gwyn describes as the Liberal Party's "worst campaigner until Stéphane Dion early in the twenty-first century", resigned after the defeat, to be replaced by Wilfrid Laurier.Under Laurier's early leadership, the Liberals, who had accepted much of the National Policy under Blake while questioning details, rejected it entirely, calling for "unrestricted reciprocity", or free trade, with the United States.