Control the water supply. That is how the debate is won.

This much was apparently advised in a memo to British Conservative Leader David Cameron in 2010, subsequently leaked to the Daily Mail. The author of the advice was a Canadian strategist named Patrick Muttart, a former adviser to Stephen Harper and one of the brighter minds credited with helping to bring the Conservative party to power here in 2006. In what Cameron’s team claimed was an unsolicited submission, Muttart apparently counselled Cameron to “practise staring down” Labour Leader Gordon Brown while the camera was focused on the moderators or other leaders, since that “makes your opponent feel uncomfortable.” When attacking or responding to his opponent, though, Cameron should “look at his opponent’s shoulder and not his face,” because “facial reactions can be distracting/destabilising.” Don’t write notes while someone else is speaking, because viewers will find that rude. Personal attacks should be well-constructed, but infrequent. Instead of “abstract ideological musings,” the candidate should “use viable, easy-to-understand solutions.” And mind the water. “Ensure Cameron has room-temperature water,” Muttart was reported to have written. “Cold water (with ice) tightens the throat. You should control his water—not the TV studio.”

Here is how the grandest stage of federal politics is managed—a hint of the fussy preparation and consideration that precedes the modern political debate. And here, perhaps, is some insight into how Harper has quietly won so many of these moments.

Beyond even the gains his party has made in each of the last three elections, the Prime Minister is, arguably, on something of a winning streak. Although he has struggled in French-language confrontations, he has otherwise come out ahead nearly every time he has been put on stage beside his rivals. Going back to 2004, he was judged to be the winner of the English-language debate by 31 per cent of respondents to an Ipsos Reid poll, 13 points ahead of Paul Martin. After a narrow loss to Martin in the first English debate of the 2006 election—32 per cent for Martin, 30 per cent for Harper—Harper won the second English debate by a count of 34 per cent to 31 per cent, according to Ipsos Reid. In 2008, Harper was deemed the winner by a leading 31 per cent, six points ahead of Jack Layton. Three years later, he posted his most decisive victory: 42 per cent of respondents gave the decision to the Prime Minister, 17 points clear of second-place Layton. (Note that, in both 2008 and 2011, the Liberal leader of the day was an also-ran: Stéphane Dion placing fourth in 2008 and Michael Ignatieff placing third in 2011.)

The potential impact of a debate is possibly more nuanced than a quick judgment of who won, but there is much to be said for winning. And while he will not be remembered as a poetic weaver of words, Harper is perhaps not given his due as a master of rhetoric and controller of the moment. Set against the complaints and challenges of his critics, Harper is smooth and unhesitating, but calm and reassuring. Ever ready with a response, he pleads for reasonableness with open palms and dulcet tones. At one point in 2011, as the debate became mired in competing claims about the nature of parliamentary governance, the Prime Minister sounded as if he might cry, as he beseeched voters to give his party a majority. “I’m worried that, quite frankly, this country, at some point, we’re going to lose our focus on the economy, start raising taxes, start doing things that are not good for the long-run interests of the country, just because of the short-run politics of a minority parliament,” he begged. He looks into the camera when he speaks and he smiles when he has a chance. If you prefer to discuss these sorts of events using boxing analogies, he could perhaps be likened to a great defensive fighter, not easily tagged and good on the counterpunch. Unexciting, but effective.

Dion was overmatched in 2008, and Ignatieff seemed unready in 2011. With a certain reliance on one-liners—“We need more zingers,” the late NDP leader told his advisers before the debates in 2011, according to Building the Orange Wave by NDP strategist Brad Lavigne—Jack Layton had good showings in 2008 and 2011, but his most effective moment was a well-timed, and barely challenged, attack on Ignatieff’s attendance in the House of Commons, one that ultimately decided who won the right to sit across from the Prime Minister in question period.

It is surely possible that the 2015 debates will present Harper with a greater challenge. Although he will come to these meetings with far more experience than his challengers, he is also, after another four years in power, more vulnerable than he was in 2008 or 2011. Since that second debate in 2006, he has come to stage with a lead. In at least the first debate, he will be the underdog. And over the last few months, Harper has seemed in the House to be a man who is conscious that he must fight to keep his job—more aggressive, more urgent—which perhaps portends a more combative debater.

His competition is potentially strong—at the very least, intriguing. NDP Leader Thomas Mulcair, widely noted for his QP performances and touted by Brian Mulroney as the best Opposition leader since John Diefenbaker, is the most aggressive challenger Harper has faced, and he has shown some ability to think on his feet. One pre-debate poll even made the NDP leader the favourite—37 per cent of respondents telling pollster Nik Nanos’s firm that they expect Mulcair to win a leaders debate, compared to 26 per cent for Harper and just 16 per cent for Green Party Leader Elizabeth May. The fast-talking and undaunted NDP leader will also come to the first debate as the presumptive favourite to become the next prime minister after this fall’s vote. That is an idea he can either conﬁrm or undermine.

The stakes for the third-place Trudeau are different, but similar. The Conservatives have expended great effort portraying him as an unworthy goof, and now he can either confirm or exceed that portrayal. New to the arena and relegated to a few questions, Trudeau struggled within the confines of question period to establish himself beside the leading clash of Mulcair and Harper, but he is also supposed to be something of a skilled and likable communicator. And the televised debate is something different than the cacophonous confrontation of QP.

And then there is May. She was last seen in a leaders debate in 2008, and it might be remembered that she was an interesting challenge for the Prime Minister then, not only as a source of pointed criticism, but as a changer of the dynamic. Bruce Carson, a former adviser to Harper who participated in preparing the Conservative leader for the 2008 debates, has written in his political memoir, 14 Days, of worrying that one wrong move with May could ruin the Conservative party’s efforts to build support among women.

Set against relative parity in opinion polls and the first real three-way race in federal history, there are struggles within the struggle here: Mulcair and Trudeau have not only to best Harper, but also each other, and May might like to see the Greens win more than one seat this fall. But it will surely be most interesting to see whether anyone can beat the Prime Minister, who, presumably, will be well-prepared.

Pending water temperature, it is perhaps down now to who chokes.