OTTAWA — Politicians approach elections the way other people go to the movies. No matter how many times they've done it, they're always looking for a new plot twist or a surprise ending.

They could be disappointed this time.

Certainly, if current opinion polls are any guide, the coming campaign is likely to deliver something everybody has seen before -- a minority government.

The odds are it will be a Liberal one, but the numbers are close enough that the balance could tip to the Conservatives.

It's an open question whether either result would produce better or more stable government in Ottawa.

The best bet for at least a longer-lasting government may be another Liberal minority, with the NDP taking enough seats to hold the balance of power in the 308-member House of Commons.

"If the Liberals and New Democrats can form a majority together, frankly, we could have good government,'' says Barry Kay, a political scientist at Wilfrid Laurier University.

"But I'm not saying it's going to happen.''

At first blush, it doesn't seem hard for Prime Minister Paul Martin and New Democrat Leader Jack Layton to swing the numbers and forge an alliance.

The Liberals, who held 133 seats at dissolution, and the NDP who held 18, would need just another four MPs between them to have effective control of the House.

It's when you start asking where those seats would come from that things get difficult.

The Liberals have been decimated in Quebec by the sponsorship scandal and will be lucky to avoid losing even more seats to the Bloc Quebecois than they did last time.

It's not just that the tide of public opinion is running against the Grits, it's also that so many of their former backroomers have been discredited.

"Because of the scandal, their organization on the ground is very shaky,'' says Michael Behiels, a University of Ottawa historian who specializes in Quebec.

"They need to recruit a whole new generation of young Liberals, and they don't have enough time.''

Next door in Ontario the Liberals are in far better shape, with 74 seats at dissolution to 23 for the Conservatives.

But Liberal strength is concentrated in Toronto and other urban centres, while the Tories are running neck and neck in rural and small-town ridings.

Martin could have a tough time picking up new seats and could even lose some old ones, says Henry Jacek, a McMaster University political scientist.

"If the Liberals go down by three or four points (in vote percentage) and the Conservatives come up by that much, that could produce a change of 30 seats.''

Liberal strategists don't see much room for improvement in Atlantic Canada; Alberta remains a wasteland for the party; prospects in the rest of the Prairies are modest to non-existent.

That leaves British Columbia, where the three federalist parties are split almost evenly going into the campaign, as one of the few hopes for Liberal gains.

The NDP is also targeting B.C., along with Saskatchewan, in an effort to boost their seat total. But like the Liberals they'll need favourable splits in three-way races to unseat incumbent Conservatives.

If it's difficult to make the arithmetic work for the Liberals and NDP, it's even harder _ though not mathematically impossible _ to figure out how the Conservatives could form a government.

It's a given that leader Stephen Harper would need to move beyond his western base and boost his seat total in Ontario. It's also a given that he'll need to overcome massive voter resistance.

Martin held Ontario in 2004 by painting Harper as a right-wing extremist, heading a party that was anti-woman, anti-gay and ready to play fast and loose with the Charter of Rights.

"The big question is whether the Liberals are going to be able once again to pull the fear card out of the pack,'' says political scientist Heather MacIvor of the University of Windsor.

"There are huge imponderables here.''

Even if the Tories succeed in breaking through in Ontario their troubles wouldn't be over.

They'd still have to figure out who to turn to for support to keep a minority government ticking over.

"They could work with the Bloc, but for how long?'' says Don Desserud, who teaches political studies at the University of New Brunswick.

"We could end up with the same type of unstable House we have now, but even worse.''

The one thing both Martin and Harper want the most -- a majority government with no need to make any deals with other parties -- seems so far out of reach it's all but impossible.

The problem, says Allan Tupper, a political scientist at the University of British Columbia, is that the geographically fragmented voting patterns of 2004 show no sign of changing.

"We have a variety of regional electoral maps, each with its own different partisan competitions -- and all of which, put together, make it difficult for any party to win a majority.''