That pits him against his boss, the prime minister, who will be rooting for the Calgary Stampeders to win this Sunday's Grey Cup.
During a speech to a Toronto business audience today, Flaherty said he'll be returning to the city to watch the centennial of the CFL championship.
Flaherty's vow to "come back for the Argos" drew applause and whoops of laughter from the hometown crowd.
Flaherty, who represents nearby Whitby-Oshawa and is a former Ontario finance minister, wrapped up his speech on Canada's upcoming budget with one last cheer of "Go Argos!"
Harper, who grew up in Toronto, said earlier this week that he cried after the Toronto Argonauts' stunning loss to the Calgary Stampeders in the 1971 Grey Cup.
But Harper says he'll be siding with the westerners when the two teams meet again this weekend.
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