OTTAWA - The Conservative government launched an all-out air war, web war on Tuesday and may toss in an old fashioned nationally televised prime ministerial address to save itself.

Gov. Gen. Michaelle Jean -- the target of much of the Conservatives' furious lobbying -- cut short a state visit to Europe and will return to Ottawa on Wednesday to deal with the unprecedented parliamentary meltdown.

She should expect to find outraged Conservatives waiting for her outside the gates of Rideau Hall.

A far more pugnacious Prime Minister Stephen Harper said he will fight a coalition threat to his government by mobilizing public opinion against what his party calls the "imposition of radical new government without the people's consent."

A formal Liberal-NDP coalition, led by Stephane Dion and backed by the Bloc Quebecois, says it will defeat Harper's minority at the earliest opportunity and then ask the Governor General to give it the chance to govern.

The Harper government has appeared to be reeling for days. On Tuesday, the prime minister fought back with a frantic 11th hour effort to paint the coalition as utterly lacking in democratic legitimacy.

The Tories launched English-language radio ads, staged small rallies around the capital, blitzed radio call-in shows and promoted a massive weekend demonstration called RallyforCanada. An official said Harper may take to the airwaves in a national TV address.

The government also announced, in conjunction with Ontario, a special adviser on the auto crisis and restructuring plans.

There are limited survival options for Harper's minority. His Conservative government has lost the confidence of the majority of MPs in the House of Commons but not yet permitted the formal expression of this non-confidence in a parliamentary vote.

What took place Tuesday in the Commons was full-throated battle rhetoric.

"The highest principal of Canadian democracy is that if you want to be prime minister, you get your mandate from the Canadian people -- not from Quebec separatists!" Harper thundered across the aisle at Dion.

The Liberal leader responded by quoting the prime minister's own words from 2005, when Harper as Opposition leader said avoiding confidence votes in the Commons was a "'violation of fundamental constitutional policies and principals in our system.'

"Is he in agreement with himself?" Dion needled.

As strange, unheralded and unwieldy as the proposed Liberal-NDP-Bloc coalition may be, constitutional experts are unanimous that its installation as an alternative government is well within the letter of Canada's parliamentary system.

The combined Commons majority, agreeing that it has lost confidence in the Harper government because of a provocative economic update, has written Jean asking that she install them in power rather than forcing Canada into its second $300-million election in two months.

The current tempest may be unprecedented in Canada's federal history, but the Governor General appeared to be taking the looming crisis in stride.

"This is part of our democratic system," Jean told CBC on Tuesday before departing from Prague for Ottawa.

"The role of the Governor General is to make sure that our governance is on the right path. So as soon as I'm back I will fulfil my duties in total, sound judgment."

The pressure on her slender shoulders is going to be immense.

The Conservatives are counting on public outrage to create dissension and doubts within the fledgling coalition.

They're also cultivating second thoughts for a Governor General who is plumbing uncharted constitutional depths. Without naming Jean, government officials are adamant that a new election must be called if the Tories fall.

"Our position is very clearly that it's undemocratic to change the government in this way -- in this radical way -- without going back to the people," a Harper spokesman said at a background briefing.

"It's an affront to democracy. It's an attack on our democracy."

In an effort to inflame public sentiment and drive a wedge into the coalition, the Conservatives are also pounding away at the theme of Dion -- who earned his political spurs as a defender of national unity -- in bed with the separatist Bloc.

Harper invoked the names Tory and Liberal prime ministers Sir John A. Macdonald, Sir Wilfrid Laurier, John Diefenbaker and Pierre Trudeau to warn Dion that he was "betraying the best interests and the best traditions of his own party" by making a deal with Duceppe.

And -- at least in English -- the Conservatives repeatedly stated that the Bloc will have a "veto" over every policy of the new coalition.

In French, however, Public Works Minister Christian Paradis cited a Liberal MP to claim that "the leader of the Bloc has signed a blank cheque and given away his independence."

During an extraordinary head-to-head exchange later during question period, Dion and Harper debated the Quebec angle at length. Dion, his voice cracking, was sputtering with rage while pointing out the contradictory Conservative messages for French and English Canadian audiences.

"He's saying that we Liberals are solding Canada to the separatists -- and his Quebec MPs are saying that the separatists are solding (selling) their soul to the Liberals! He needs to choose between these two lies."

The National Citizens Coalition, which Harper used to head, is publicly advocating that Parliament be prorogued -- or dissolved -- until the end of January. The right-leaning advocacy group is urging citizens to directly lobby the Governor General to that end.

The Conservatives refuse to even utter the word "prorogue." But they also refuse to rule it out, saying repeatedly that they'll pursue "every legal means" to avert defeat.

"That's the million-dollar question," said one Conservative insider.

Such a tactic would require some pretzel logic from Harper.

As Opposition leader, he argued convincingly in 2005 that the Liberal minority of Paul Martin should be able to earn the confidence of the Commons every day.

Exactly a week before a May 18, 2005, confidence vote, Harper expressed outrage that the Liberals were delaying an expression of Parliament's will.

"The government has lost the moral authority and the democratic legitimacy to govern," said Harper. "They cannot carry on. It is time, for God's sake, to go."

And in September 2004, Harper wrote a joint letter with Layton and Duceppe to the governor general asking Adrienne Clarkson to consider letting the Conservatives form a government if the Liberals fell. No election would be necessary.

"The Governor General does not have to follow the prime minister's wishes," Harper said after meeting to discuss the matter with Clarkson.

"She must ensure that he has the House's confidence, that's all."