I remember reading that around 2002 (or possibly early 2003), when the Martinites were being really aggressive in trying to force Chretien out of office, this had the opposite effect on him psychologically. Chretien seriously considered calling a snap election and leading the party through another campaign (backing off on his pledge that 2000 would be his final campaign) to more than anything assert his leadership.
While it's possible that Chretien would take a fair amount of heat from the public for calling an election as little as two years after the previous one, the Liberals were still doing very well in 2002 and early 2003 IOTL (with the Alliance often polling behind the PCs, and the Bloc continuing their downward trend; in fact, I think the Liberals were the only party consistently polling above the low twenties, and by a wide margin) that I think they'd still win a fairly easy majority government even with any early-election backlash. Besides, even then I could imagine Chretien framing the election as a referendum on his leadership, of sorts, which he could be excused for given the publicity of the Martin insurgency.
If he won (which I'm nearly certain he would), I'm skeptical that he would serve out the full four years (probably retiring around 2005), but if he did frame the election as a referendum on his leadership the Martinites would likely be far more weak than OTL.