After what may have been the briefest leadership race in Canadian history, Bloc Québécois Leader Gilles Duceppe will on Monday tell his caucus why he so briefly vied for the top Parti Québécois job.

Duceppe was a PQ leadership candidate for only about 24 hours, but he dropped out on Saturday - the day after announcing his bid to the press - in order to make way for former Quebec cabinet minister Pauline Marois.

Gilles Duceppe has said he didn't want to divide the sovereigntist movement by running against Pauline Marois.
(Jonathan Hayward/Canadian Press)

Marois, 58, officially announced her candidacy on Sunday.

Duceppe's on-and-off leadership bid may have caused many Bloc MPs to scratch their heads. It even caught some of his friends and advisers off guard.

"Surprised? My arms fell off," said former Bloc MP Richard Marceau, chuckling. "I was really surprised."

But Marceau said that in the end, Duceppe's decision to step aside for Marois was a good one as it keeps Duceppe in Ottawa.

"People thought without him at the helm of the Bloc, the Bloc would be much weaker and it wouldn't be good for the sovereignty movement as a whole," he said.

The Bloc leader said he didn't want to risk dividing the sovereignty movement by running against Marois, a longtime PQ member who held the province's most important portfolios - including finance, health and education - while the party was in power in the 1990s.

But the political damage to Duceppe's reputation due to the abrupt turnaround has been done, political commentator Josée Legault said.

"I think that Mr. Duceppe will come out of this in the short term weakened both in the caucus and in the House of Commons," he said. "I mean, Mr. Harper is going to have a field day with this in question period."

Meanwhile, Bloc MPs are trying to put a positive spin on their leader's reversal, praising Duceppe for his boldness in making such a public about-face.