Stephen Harper pleaded with Ontarians to resist the New Democratic Party's surge and give him a majority, invoking the NDP record during the Bob Rae years in order to scare voters away from Jack Layton.
It's a pitch he began using last week and amplified during his last campaign stop in Ontario Sunday.
"Ontario has had that experience and Ontario can help make sure it does not happen to our country."
Mr. Harper was on a final cross-country campaign push that was to end in Abbotsford, B.C. Sunday night.
The Tories are hoping bad memories of the early 1990s Rae government in Ontario - as the province was mired in recession - will scare voters into switching to the Tories.
"Ontarians know from bitter experience how devastating it can be for workers and families when an inexperienced NDP government suddenly finds itself in office," Mr. Harper told a crowd of more than 400 near the London, Ont., airport.
"Folksy talk, grandiose promises from an untested party on the campaign trail - soon to be replaced by the sobering reality of crushing taxes, out-of-control deficits, massive job losses," he said.
The Conservative leader's central campaign message in this race is based on a hypothesis: If he doesn't win a majority government his rivals will unite to displace him.
The Tories are targeting Mr. Layton because they're directly competing for votes in ridings across the country from Nova Scotia to British Columbia.
Speaking to Londoners, Mr. Harper cautioned voters that a vote for the NDP could have far-reaching consequences this time.
"A vote for the NDP is not some kind of experiment; it is a vote for an NDP government," Mr. Harper said.
The lastest poll numbers from Nanos research show the Tories at 37 per cent nationally with the NDP in second at 30.6 per cent and the Liberals third at 22.7 per cent.
The revised Tory campaign pitch that has developed over the last few days is that the New Democrats would hurt Canadians in the pocketbook.
"Let us put it plainly: An NDP government means higher gas prices, smaller paycheques and a weaker economy," Mr. Harper told a crowd in Stratford, PEI where he began his Sunday campaigning.
He acknowledged the surprising drop in Liberal fortunes and the resulting hike in NDP support during the race, saying "this has been an unusual election."
The Conservative leader reached out to Liberal voters again, warning them their party has no hope of forming government and asking for their help to stop the NDP.
Mr. Harper predicted his Liberal rival has no hope now of winning the Prime Minister's Office.
"Mr. Ignateieff has taken the Liberal Party away from its roots and in an NDP direction and the best hope for Mr. Ignatieff now is to be a backseat passenger in an NDP government," he said.
"Let me speak very clearly to traditional Liberal voters: I know many of you do not want NDP policies. That you do not want NDP tax hikes," he said.
"That is why to make sure the economy stays on track for all of us, and the next Parliament does not raise taxes, Canada needs a stable, majority Conservative government."
Mr. Harper was scheduled to end his day in Calgary where he will await the results of Monday's election.