In the Hollywood star system, celebrity couples are a sum greater than their parts. There’s Brangelina, TomKat, Spederline. In Canada, we have IggyBob: Michael Ignatieff and Bob Rae. The two Toronto MPs aren’t physically inseparable, but metaphysically inseparable, always mentioned in the same breath by members of the chattering class. Both sons of eminent Canadian diplomats, they have been friends and rivals, yin and yang, their entire adult lives. By all accounts, their rivalry is not rooted in any significant philosophical or ideological differences; it is all about ego. It’s not about who’s better for the country; it’s about who’s better, period. Political watchers were looking forward to the showdown between them at the 2006 Liberal leadership convention, the climactic fratricidal scene of a Greek tragedy—until Stéphane Dion caught the country by surprise, emerging from also-ran obscurity to victor in the span of about 18 hours.

Since then, both men have taken only whatever share of the spotlight Dion accords them. But according to one mutual friend, their humble behaviour “is backdropped by a belief, on both their parts, that Dion is hopeless. Absolutely hopeless.” They are not alone in their view, and as Dion’s campaign stumbled in its first few weeks, news of bickering within Liberal ranks had become a serious distraction. Dissatisfaction with the leader was at an all-time high, and as one party operative put it, even if Dion didn’t completely screw up—even if the end result was another Conservative minority—“the knives would be out by mid-November. The only question is whether he’ll go quietly.” All of which explains why, in the first week of the campaign, the party executive quietly postponed the Liberals’ next policy convention, scheduled for December in Vancouver. With the possibility of a leadership conven­tion on the horizon, the party couldn’t afford the cost of back-to-back gatherings. That, and IggyBob will need time to prepare.

Ironically, if the Liberals have an advantage over the Conservatives in this campaign, it’s their team: a front bench with lots of political savvy and intellectual smarts, compared to the lightweights (Stockwell Day), hound dogs (Peter Mac­Kay, Maxime Bernier) and small men (Jim Flaherty) who surround Stephen Harper. Dion’s compromise victory at the convention merely put off the ultimate resolution of the party’s inner turmoil: which half of IggyBob will live, and which will die? Liberals are determined to find out soon. And so is Iggy­Bob.

The myth of origin goes like so: one Saturday morning in the fall of 1966, a fresh-faced 19-year-old Michael Ignatieff was holding court in a University of Toronto cafeteria, spouting off to a group of willing listeners. Young Bob Rae, overhearing him, thought he was full of it and went over to tell him so. Ignatieff responded in kind. Within months they were roommates. What has blossomed between them in the intervening 42 years looks like a friendship, but it has always retained the you’re-such-an-ass tension of that first encounter. The competition stayed friendly, if only because they were working in different spheres: Rae as an NDP leader and Ontario premier, Ignatieff teaching at Oxford and Harvard, and writing in The New York Times and The Observer. “There is a genuine affection between them,” says a friend of both men. “But I think there was an unspoken understanding, at least on Bob’s part, that Bob would be the politician and Michael the intellectual.”

That changed in 2005, when Ignatieff was invited to speak to Liberals at their convention and blew them away. “He got a taste of the political limelight, and he was hooked,” says the friend. Rae, meanwhile, was in his 10th year of political exile following his 1995 defeat as premier, and he was bitter. I met him at a luncheon around that time, and he was full of vitriol for Howard Hampton, Jack Layton and any other New Democrat you could name. He had clearly broken with his old party but had only begun the mating dance with the Liberals. Ignatieff, meanwhile, was well on his way to becoming the Liberal MP for Etobicoke-Lakeshore.

In the spring of 2006, Ignatieff met Rae for lunch to explain his decision to seek the Liberal leadership. Rae was thunderstruck that Ignatieff would consider himself qualified for the job; Ignatieff was aghast that Rae would not support his bid. At that time, Rae had been flirting with the idea of his own leadership bid; though nobody will say so directly, it appears that Ig­natieff’s candidacy pushed Rae into the fray.