Sources say it appears that Natural Resources Minister Joe Oliver might step into the Finance gig, now that Flaherty has decided to resign from cabinet.
The Prime Minister's Office would not confirm Oliver's promotion, but the 73-year-old cancelled an event that he had scheduled in British Columbia for Wednesday.
Whoever Harper chooses must keep the beat on the government's single biggest refrain _ strong, stable stewardship of the economy _ into the election campaign set for next year.
Oliver is widely respected within the Harper cabinet and among Conservatives, and is well known on Bay Street, having spent decades working there as an investment banker. He went on to become executive director of the Ontario Securities Commission and then president of the Investment Dealers Association of Canada.
But Oliver has a much different demeanour than Flaherty, and often appears gruff and highly partisan.
The government's approach to selling the Keystone Pipeline under Oliver was first punctuated by attacks against environmental groups. Now critics, including Saskatchewan Premier Brad Wall, have been calling on Ottawa to shore up their environmental cred to win favour with Washington.
The opposition, meanwhile, is keen to see who takes on the job and where that person lines up ideologically compared with Flaherty.
NDP finance critic Peggy Nash said Flaherty's departure means one less voice of opposition to income splitting in the Conservative cabinet.