The federal election in Canada started as an election of image, but since one man seems to have won that battle, the campaign is shifting to issues. The biggest issue of all is the economy.
The man who seems to have won the battle of image is Brian Mulroney, the leader of the opposition Progressive Conservative Party. The man who is bringing up the economic issues, pressing Mr. Mulroney to answer questions, is John Turner, the prime minister and newly elected leader of the ruling Liberal Party.
Polls published this week indicate Mr. Mulroney and Mr. Turner may be switching jobs after Sept. 4. They suggest the Tories will gain at least 180 of the 284 seats in the House of Commons.
Turner and some of his leading candidates have been warning Canadians about ''a secret agenda,'' should the Conservatives take power. Liberal Party president Iona Campagnola, a candidate in British Columbia, and Jean Chretien, are both saying the right wing of the Tory party is ready to slash social programs and bring in tax laws favorable to big business. On Wednesday, Turner proposed a minimum tax of 13 percent for people making more than $60,000 a year.
The Liberals are launching a television advertising campaign asking whether Canadians can trust Mulroney. They will point out that, if elected, he would be dealing mainly with Tory premiers in the provinces. The Liberals say he has worked out an energy deal with Brian Peckford, Tory premier of Newfoundland.
This week Turner cited ''a quiet little accord'' - quoting words used by a prominent Conservative - on energy issues. He said such deals would mean the end of generous federal tax help for offshore exploration in provinces such as Newfoundland and Nova Scotia.
''The very future of offshore development is threatened,'' Turner warned.
The Tories have attacked the Liberal record on energy, especially the National Energy Policy, for which they blame many of Canada's economic woes.
The Canadian economy has not rebounded as quickly as the United States economy. Unemployment is at 11 percent here, 7.5 percent in the US. Estimates put this year's growth rate at 4 to 4.5 percent in Canada, 6.5 to 7 percent in the US.
''If it wasn't for the spinoff from the strong US economy, the Canadian economy would be flat on its back,'' says Carl Beigie, economist with Dominion Securities in Toronto. He attributes the US performance to ''confidence.''
''Reagan has the Americans feeling they can do anything again,'' Beigie says, adding that Pierre Trudeau hasn't built the same confidence in Canadians.
Turner inherited the mantle of Mr. Trudeau, even though the two men disagreed on basic economic policy just before Turner resigned as minister of finance in 1975. The Liberals are being blamed for the high interest rates and high inflation of the last four years, even though inflation at least has calmed down.
Turner has asked Mulroney to cost his election promises. Mulroney has denied charges they would cost $20 billion. He has promised to announce on Aug. 28 how much his election promises would cost.
It is thought that even if he bungles that issue, it will be too late for the Liberals to capitalize on it. Even the most dedicated Liberals are saying privately that the best they can hope for is a minority Conservative government.