The NDP is on the verge of a historic election win in Nova Scotia, which would the first time the party formed a government in any of the Atlantic provinces.

Polls show the NDP well out in front, followed by the Liberals, and the Progressive Conservatives, who have been in power for a decade, trailing in third.

The election is on Tuesday, and politicians were still out banging on doors Sunday afternoon.

NDP Leader Darryl Dexter, whose party is expected to do well in urban areas around Halifax, said Sunday he was making an extended effort to connect face-to-face with rural voters.

"Sometimes in the last 48 hours in can make the difference in the campaign," he told CTV Atlantic.

In hockey-mad Nova Scotia, where local boy Sidney Crosby of the Pittsburgh Penguins is treated like a deity, the Liberals brought out their own hockey heavyweight on the campaign trail -- federal Liberal MP Ken Dryden.

While Liberal Leader Stephen McNeil, 44, was out on Sunday lending his support in ridings that were expected to be tight, PC Leader Rodney MacDonald, 37, will remain in his home riding in rural Cape Breton until campaign day.

A Nova Scotian pollster says the shift in voter intentions, represents a substantial shift in political allegiance in the province.

"The major theme is change, and change in a substantive way," Halifax pollster Don Mills told The Canadian Press.

Mills said his own polling suggests significant dissatisfaction with the Tories, whose minority government fell on May 4 on a fiscal bill that would have allowed the province to run a deficit at the cost of avoiding legally required debt payments.

"Traditionally, when Nova Scotians were dissatisfied with their government they turned to the other party that governed -- Liberal or Conservative. But this time we see a move to a group that has never had the opportunity to govern."

Divisive ad campaign

The election took an ugly turn in its final days, with scathing attacks ads and counter threats of legal action.

The Tories are running radio ads claiming the NDP got "$45,000 in illegal money from union bosses."

Last week the NDP returned the money it received from several unions belonging to the Mainland Building and Construction Trades Council after staff realized the donations may have broken campaign rules.

Under election rules a trade union can only make a single donation of $5,000.

MacDonald calls it "a cloud" over the campaign of Dexter, a 51-year-old former journalist and lawyer.

But the NDP says the ads go too far, and that they are defamatory. The party sent out legal letters to radio stations on Friday insisting the ads be pulled off the air immediately. They're threatening more legal moves unless there's an apology and on-air retraction.

Dexter says the Tories "greatly miscalculated" and insists the negative ads are driving voters further away from the Conservatives.

The Conservatives say the ads will keep running and they stand behind the content.

In the dying days of the campaign MacDonald compared Dexter to a car thief who had to return his ill-gotten gains.

Nova Scotia's Chief Electoral Officer is investigating, but won't rule until after the election is over.

During the campaign MacDonald labeled the NDP a tax-and-spend party with more than $2 billion in campaign promises and appealed to voters not to risk the economy with the NDP.

Dexter said the real risk was four more years of Conservative rule.

At the dissolution of the legislature, the Tories had 21 seats, the NDP 20 and the Liberals, nine. There was one Independent and one seat was vacant.

With reports from CTV Atlantic and The Canadian Press