As they gather in Toronto this weekend, Canada’s New Democrats are about to do something they’ve never done before: Name the next leader of the Official Opposition.

Interestingly, it was 10 years ago Tuesday, on March 20, 2002, that the Canadian Alliance also elected a leader of the Official Opposition. His name was Stephen Harper.

And though Harper’s success was not inevitable at the time, the broad assumption a decade ago was that, if Jean Chretien and the Liberals were ever to be beaten, it would be by a conservative party and certainly not by the New Democrats, then led by Alexa McDonough.

But when the Conservatives fall out of favour — and everyone knows that time will one day come — can we assume it will be replaced by another Liberal government?

For the first time in our history, the answer to that question is no.

Whoever is crowned NDP leader Saturday will wake up Sunday in charge of a well-organized, well-funded party machine. He or she will have a sizeable parliamentary budget to advance the NDP cause and, not insignificantly, can plan a move-in day at Stornoway, the official home of the leader of the Opposition.

More importantly, he or she will reasonably make the claim in Saturday’s victory speech to be the only serious alternative to Stephen Harper to become the next prime minister of Canada.

Some might giggle at the idea of an NDP prime minister. You shouldn’t.

New Democrats, more so than Liberals, have carefully watched how, in the decade since becoming a party leader, Stephen Harper built what is now the most fearsome political machine in the country. New Democrats have watched, learned, and, in many cases, emulated some of the blue team’s methods and tactics.

And, like the Conservatives, New Democrats have a decade’s worth of electoral success to show for their hard work.

Consider: In 2000, Jean Chretien would win the last Liberal majority on the strength of having convinced 5.25 million Canadians to vote for him. The combined Alliance and Progressive Conservative vote that year totalled 4.84 million. Alexa McDonough’s New Democrats finished that race with a disappointing 1 million votes.

In the four federal elections since, the Liberals have done worse every time and by 2011, 2.5 million Canadians who had voted Liberal a decade ago were voting for someone else.

The Conservatives, united for the 2004 campaign, showed gradual improvement and, last spring, won their majority with 5.83 million votes.

In the intervening decade, Harper has found

988,000 new votes for the country’s Conservatives.

Meanwhile, the NDP vote doubled in 2004 compared to 2000 and steadily improved until the breakout last spring when 4.5 million Canadians cast a ballot for a New Democrat.

Harper’s critics fret that the country has moved to the right. Really?

Harper has convinced fewer than a million Canadians to move right in the last decade, while Jack Layton convinced a whopping 3.4 million Canadians to move left to vote NDP in same period.

Moreover, a New Democrat looks a good bet to win the premiership in B.C. next year.

A New Democrat is premier in Manitoba and Nova Scotia. New Democrats are the official opposition in Saskatchewan and hold the balance of power in Ontario.

Still think you should giggle at the newly crowned NDP leader’s victory speech this Saturday?