Premier Jean Charest hammered away at a familiar theme during a campaign stop, saying the Liberal Party is the only choice for those who want economic stability.
Charest said the Parti Quebecois or Coalition for Quebec's Future wouldn't have "any positive impact" on trade relations with other provinces or the United States.
Charest, who is trailing in some recent opinion polls, told a rally in the Outaouais region in western Quebec that it's up to voters to decide in the Sept. 4 election if they want the instability brought on by another sovereignty referendum.
Francois Legault, head of the new Coalition party, spent much of the day campaigning in the same area as Charest, traditionally a Liberal stronghold.
Legault said Charest must be nervous to devote a day to the predominantly federalist area.
"I think Mr. Charest is feeling the heat," he said.
Meanwhile, Parti Quebecois Leader Pauline Marois, who places ahead of both Legault and Charest in some recent polls, called on all progressive voters to help get her a majority mandate.
The PQ is facing the danger of having some votes siphoned off by smaller parties such as the hardline sovereigntist Option nationale and the social-democratic Quebec solidaire.
Marois campaigned Sunday in the Montreal riding of Gouin, where the PQ is facing a stiff challenge from Quebec solidaire's popular co-spokesperson, Francoise David.
Marois was forced to backtrack after suggesting, in response to questions from the media, that conservative-minded sovereigntists should look elsewhere than the PQ.
A little over an hour later, she called reporters back to clarify, and encouraged right-leaning sovereigntists to vote for her party.
"I have one thing to say to conservative sovereigntists," she said. "The Parti Quebecois has always run the province in a responsible manner."
Advance voting for the election was held Sunday and is available again on Monday.
- with files from Patrice Bergeron, Fannie Olivier and Martin Ouellet
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