Political rookie Nicolas Marceau delivered the goods for the Parti Quebecois on Monday evening, cruising to victory in a byelection northeast of Montreal.

Marceau grabbed 57 per cent of the vote in Rousseau, compared with 31 per cent for Liberal candidate Michel Fafard.

Marceau, a 45-year old economics professor, will replace onetime PQ minister Francois Legault, who had held the riding for nearly ten years before leaving politics in June.

PQ insiders say Marceau is potential cabinet-minister material.

"Clear cut victory," said Marceau, a UQAM professor with four children.

"We got the same percentage that Francois Legault had in the last election.

"So I'm very happy, I'm very satisfied. All is fine for me tonight."

Boost

The win is a welcome boost for PQ Leader Pauline Marois, who has been watching her poll numbers sag all summer.

"I'm very happy," she told reporters in St-Lin-Laurentides on Monday evening.

"It's a great pleasure for me. We had a very good candidate and now he wins tonight and he will be a very good member of the national assembly."

The win was not totally unexpected. The PQ has held Rousseau riding since 1994.

The Liberals thought they had a chance at an upset and ran an aggressive campaign with Farfard, a well-known local candidate.

He also ended up with much the same numbers he had last time around.

Liberal cabinet minister Michelle Courchesne said the Liberals could take some solace from the loss.

"The population knows now that the Liberals are here to stay," she said.

"We have a good organization, a lot of people working for the party, a great candidate and we'll be staying here."

ADQ plunge

The ADQ continued its nosedive, getting less than five per cent of the vote in the predominantly francophone riding north of Montreal and barely beating out the left-leaning Quebec solidaire.

The ADQ had 16 per cent in Rousseau in last December's general election and 38 per cent in 2007.

- With files from The Canadian Press -