With various minority government scenarios now playing out on the campaign trail, one man could emerge as the ultimate decider: Governor-General David Johnston.
Mr. Johnston, who was chosen for his constitutional knowledge and level-headedness, may now have to put that knowledge to the test: He could be forced to decide who governs Canada and when there will be another federal election - powers many Canadians may not be aware the Governor-General possesses.
"He has the advantages of a deep knowledge of our constitution and parliamentary conventions, access in confidence as required to the finest advisers in the country, and decades of experience in facing and resolving difficult issues," said Rob Prichard, a friend and the former president of the University of Toronto. "From my perspective, the office could not be in better or sounder hands."
Constitutional experts are not willing to speak on the record, on the grounds they may be called upon to advise the Governor-General in the event of a parliamentary crisis. But precedent both in Canada and in other Westminster parliamentary democracies will guide events.
FIRST, A THRONE SPEECH
If the Conservatives win the most seats in the House of Commons but fail to obtain a majority, Mr. Harper would remain prime minister.
He would face the House and present a Throne Speech, laying out his government's agenda, which the Conservatives say would certainly include reintroducing the budget that the opposition parties refused to support in March.
ENTER, THE GOVERNOR-GENERAL
If the opposition combines to defeat the Throne Speech, or if it lets the Throne Speech pass but defeats the budget, then Mr. Harper would have no option but to visit Mr. Johnston and tender his resignation.
If he advises that Parliament be dissolved and another election held, Mr. Johnston would reject that advice. One of the chief responsibilities of the Governor-General is to make Parliament function after an election.
WHO FORMS GOVERNMENT?
His next step would be to summon Mr. Ignatieff, assuming the Liberals were the second party in the House, and ask him if he could form a government. By this time, the Liberal Leader would certainly have consulted with NDP Leader Jack Layton and Bloc Québécois Leader Gilles Duceppe. Presumably, he would have their agreement to support a Liberal Speech from the Throne and budget.
In that case, Mr. Johnston would ask Mr. Ignatieff to form a government.
FOR HOW LONG?
Over the coming weeks and months, as a Liberal government attempted to retain support from the smaller parties or even from the Conservatives, the Governor-General would continue to encourage Parliament to keep working. Six months is generally considered the minimum time that should elapse between elections.
In any eventuality, say those who know both parliamentary conventions and Mr. Johnston himself, he would attempt above all else to encourage political solutions brokered by the politicians themselves. Which speaks to another unwritten law of Parliament: The less role the head of state in Canada plays in governing, the better.