OTTAWA -- Very few federal politicians are planning to get involved in the upcoming Quebec election campaign, with one of those notable exceptions being Justin Trudeau.
   In the face of an unpredictable three-way race, and an untold number of potential consequences for Canadian politics, federal parties will tread carefully starting Wednesday when Premier Jean Charest is expected to call a vote for Sept. 4.
   The premier has all but made it official. Seeking a rare fourth term, Charest was nominated late Tuesday as a Liberal candidate in Sherbrooke, Que., where he faces a tough battle in his own riding.
   "When we announce the elections we will inform you," Charest told reporters earlier in the day. "And it won't be very long."
   Outside his nomination meeting, student protesters gathered for a peaceful demonstration. Many more protests are expected during the campaign, which will be held against the unpredictable backdrop of student strikes.
   Federal parties are aware of the potential for the noise to spread to the national-unity front, where a decade of relative calm could end in several weeks' time.
   While recent polls place support for independence below 50 per cent, and suggest the issue is low on voters' priority list, there are hints of choppy political waters ahead.
   The pro-independence Parti Quebecois enters the campaign as the presumptive front-runner and has wasted no time declaring its plan to pick fights with the Harper Tories, should it get elected, in an effort to stir nationalist passions.
   The PQ has tossed another unpredictable element into the mix: a plan to allow more frequent referendums, as initiated in many U.S. states with citizens collecting petition signatures, and it's far from clear when that moment might arrive or how the federal government might prepare for it.
   Whenever Quebec has held a vote on independence, the sovereigntists' main foe in the Prime Minister's Office has been a Quebecer. The first time they faced Pierre Trudeau, who delivered a 1980 referendum campaign speech best remembered for the line, "My name is a Canadian name."
   Trudeau's son will play a far more limited role in this Quebec election campaign. Justin Trudeau is only preparing to help out his provincial counterpart in the urban Montreal riding of Papineau.
   The prominent Liberal MP, a potential leadership candidate, is ready to appear at public events with provincial Liberal Gerry Sklavounos if he's asked, a spokesman said Tuesday.
   "Of course, we'll be involved a bit," said Louis-Alexandre Lanthier. "We have a good relationship with our local (MNA)."
   As for other federal politicians, most are claiming neutrality.
   The Conservatives are proceeding carefully. Aware of the potential challenge ahead in Quebec, where his party holds few seats, Prime Minister Stephen Harper recently met with Brian Mulroney to discuss strategy in the province.
   An early strategic choice, it appears, is to avoid loudly taking sides in the campaign.
   "It's a choice for Quebecers," said Julie Vaux, a spokeswoman for Harper.
   The NDP, which holds most federal seats in Quebec, also plans to steer clear. It has MPs of varying provincial stripes and, as with some other divisive Quebec issues, it will avoid picking sides. The party says it's going to concentrate on its duties as the federal Opposition.
   "My role as an NDP MP is to continue the fight against the retrograde and dangerous policies of the Conservative government of Stephen Harper," NDP MP Alexandre Boulerice, a former member of left-wing, pro-independence Quebec solidaire, wrote in an email.
   "Our energy and attention is completely devoted to our role as Official Opposition."
   NDP Leader Tom Mulcair, a former environment minister in Charest's government, has picked his battles carefully when it comes to Quebec, keeping his party mainly out of the student dispute in the province, for example.
   As for the Liberals, not everyone is getting involved.
   "It's not up to me to open my mouth and speak for a provincial party," said Montreal MP Marc Garneau who, like Trudeau, could be a leadership candidate. "It's their election and it's up to them to decide their strategy, their policies and how to run their campaign."
   The Bloc Quebecois, on the other hand, makes no bones about its allegiance. Bloc Leader Daniel Paille says his troops will help out the PQ.
   "Each of our MPs are encouraged to make an effort if they want to help the candidate in their riding," Paille said, adding that "the Bloc has limited means."
   The party's machine isn't quite the force it once was, since the Bloc only elected four MPs in the last federal election.
   The PQ is working to replenish the sovereigntist ranks.
   The party has named a number of high-profile candidates in recent days, adding a labour leader and media personality to its roster Tuesday.
   One is Jean Poirier, a spokesman for workers at Aveos Fleet Performance Inc., who lost their jobs when the aircraft-maintenance company shut down this spring. Following the shutdown last spring, he accused the federal government of shirking its legal responsibility to protect those jobs.
   Poirier plans to fight his next battles in his natural political home.
   "I was born a sovereigntist," said Poirier, who will run in a difficult race against Quebec solidaire leader Amir Khadir. He accused Khadir's party of dividing the left-wing, sovereigntist vote and he encouraged voters to rally behind the PQ.
   "I voted Yes in 1995 and I believe we must continue toward the next time."
   The other PQ recruit is Sophie Stanke, an actress and journalist who will run in a Montreal riding won handily last time by the Liberals.
   The new Coalition Avenir Quebec (Coalition For Quebec's Future), which was leading opinion polls earlier this year but is now in third place, also announced well-known recruits Tuesday.
   Dr. Gaetan Barrette, the head of the province's medical specialists union, and Claire Samson, president of Quebec's association of film and television producers, will run for the Francois Legault-led party in the 450 ring around Montreal.
   The presence of Legault -- a former PQ minister who promises not to raise the independence issue -- adds an unpredictable variable to the race.
   With the relatively close poll numbers, and the potential for numerous three-way vote splits, it's anybody's guess what political dynamic the country might wake up to on Sept. 5.
   A victory by the Quebec Liberals would certainly prompt a sigh of relief from Ottawa. Even if Harper has pledged to work with any elected government, including the PQ, a referendum threat would likely drain considerable political energy.
   In any case, the federal Tories' lack of popularity in Quebec makes it difficult for them to get involved. Any direct involvement by the federal Conservatives is likely to be seen negatively by Quebec voters.
   "They'll stay very far away from the provincial election," said Patrick Clune, a former Conservative candidate and now a political analyst for a radio station on Montreal's south shore.
   "They won't touch it."
   In previous federal elections, they had depended on close ties with the Action democratique du Quebec to make inroads in the province. But ADQ support collapsed in recent years, and the party was eventually gobbled up by the CAQ.
   ADQ supporters have since splintered, with some finding their way to the Liberals and others opting to stay with the new party.