The three major federal parties, and one business-based right-of-centre group that calls itself, oddly, "Working Canadians," unleashed political television ads on Monday.

Those ads serve to remind us that we're well into what will certainly be Canada's longest election campaign ever.

Getting such an early start on the campaign -- the fixed election date is October 19, five months away -- might motivate some voters.

For many, however, it is mostly a cause for anxiety.

It reminds them of their profound disaffection with the current Conservative government, and that the dreaded day of decision is coming.

This writer has never, in many years following Canadian politics, seen a situation where so many people were so apoplectic at the prospect of the current government returning to power.

Louis St. Laurent, John Diefenbaker, Lester Pearson, Pierre Trudeau, Brian Mulroney, Jean Chrétien and Paul Martin: they all had their detractors.

But none elicited the kind of loathing and fear -- worse than fear, in fact, utter dread -- that Harper does.

Fear of a 'split vote'

One manifestation of that dread is the concern that, in a three-way race, the Liberals and New Democrats will "split the vote," and Harper will slip back into power, if only at the head of a "minority government."

This writer hears that concern expressed over and over again.

But it may be overblown.

That's not because the Conservatives could not possibly win the largest number of seats in October.

It is because even if they do win a plurality but not majority in October, it is not likely Harper could get one of the other parties to vote confidence in his government, and, ergo, allow him to remain in power.

Immediately following the election of 2008, Prime Minister Harper, at the head of a strengthened minority and facing a weakened Liberal Official Opposition, managed to get the House of Commons to vote yea to his government's speech from the throne.

In that way, the House voted "confidence" in his government.

Harper then turned around and, in his government's fall fiscal update, poked a stick in the opposition's eyes.

The update, delivered by the late Finance Minister Jim Flaherty, made the absurd and insulting claim that Canada would run a small surplus in the midst of the worst recession since the 1930s, and, for good measure, pledged to eliminate the per vote subsidy for political parties.

That arrogance and hubris so provoked the opposition parties that they promised to vote down the government, and, instead of holding a new election less than three months after the previous one, form a coalition government.

Bloc support made the 2008 coalition unacceptable

There was an Achilles heel to the coalition proposition, however.

The Liberals and New Democrats did not, combined, have anywhere near a majority. Their coalition was only viable with the support of the separatist Bloc Québécois.

Bloc support was a poison pill too many Canadians could not swallow.

And, since the House had already voted confidence in his government, Harper could credibly go to the governor general and request that parliament be prorogued -- put on ice for a few months.

Prorogation put an end to the ill-fated coalition idea.

This time the stars are aligned differently.

Let's say Harper does win the largest number of seats this October, but well short of an absolute majority of 170.

The Liberals and New Democrats, combined, would then have a significant majority of seats.

In such a circumstance, neither opposition party would have reason to vote confidence in Harper.

Tom Mulcair and Justin Trudeau will be fully aware that any continuation of the Harper regime is what is most anathema to the majority of their voters.

And so we could expect the Liberals and New Democrats to vote down the government at the first opportunity, the speech from the throne that must follow an election.

There is no rule that states when a prime minister must recall parliament following an election. Normally they do so within weeks, if not days.

Given Harper's already-demonstrated contempt for democracy we might expect him to rag the puck and delay facing the House until sometime in 2016.

But he will not have the right to delay indefinitely. Sooner or later he will have to face the music.

Whenever the opposition got to vote down his speech from the throne Harper would lose the constitutional right to remain as Prime Minister.

There would then remain only two options: a new election, or some other governing arrangement that would win the confidence of the House.

A second-place minority or a coalition

Such a governing arrangement could entail a formal coalition government of the two opposition parties; or one of the two could govern as a minority, with the support of the other, based on an agreed-to legislative program.

We have had coalition governments in Westminster-style parliamentary democracies in the past: in Britain, led by Ramsay MacDonald in the 1920s; under Winston Churchill during the War; and, most recently, the David Cameron-led Conservative/Liberal-Democrat coalition.

In the Ontario election of 1985, David Peterson's Liberals won fewer seats than Conservative Premier Frank Miller's Conservatives, but neither won more than half the seats.

After a majority of the newly elected members of the Ontario legislature voted down the Conservatives' speech from the throne, Peterson's second-place Liberals formed a minority government with NDP support, based on a legislative agreement.

That's how parliamentary democracy works.

After the next election, if we can safely assume the Bloc Québécois will be out of the picture, Canadians are not likely to be outraged by either a second-place-finisher minority government or a coalition.

That will be especially true of the majority of Canadians who had, in effect, voted to kick the Conservatives out of power.

Thus, the legitimate thing to fear is not that Harper might win a slim plurality of seats in October.

The minimum vote share to win a majority of seats

What should worry those who want to see the back of the Conservatives is that Harper would somehow win another majority.

How likely is that?

Anything can happen. The election is five months off.

But here is a statistic to bear in mind when worrying about the future of Canada following October's election.

The lowest share of the popular vote in a federal election that yielded a majority of seats was 38.5 per cent.

Jean Chrétien's Liberals got that in 1997, and won a fairly comfortable majority of seats.

In the 1997 election, no other party got even as much as 20 per cent of the vote.

The second-lowest vote share that delivered a majority of seats was Harper's in 2011: 39.6 per cent.

In the 1960s and 1970s, with vote shares of 38.5, 39.8 and 41.7 per cent, Lester Pearson and Pierre Trudeau only managed to win pluralities, which resulted in minority governments.

Polls come and go, of course.

The Harper Conservatives could still move up.

But the Conservatives' current polling numbers of 30 per cent or less could not give them anywhere near a majority, no matter how the rest of the vote "splits."

Photo: pmwebphotos/flickr