French President Nicolas Sarkozy has called for tougher borders and a stronger national identity.
The conservative leader has also accused the left of petty slander as he struggles to catch up with his Socialist rival a week before a presidential runoff.
Mr Sarkozy trails his centre-left challenger Francois Hollande by 10 points in opinion polls for the vote on May and hammered home a message aimed at the nearly one-in-five far-right voters whose support he needs to win a second term.
In a speech in the southern city of Toulouse, which was shaken in March when an Islamic gunman went on a shooting rampage, Mr Sarkozy used the word "border" dozens of times as he stressed that love of one's country should not be confused with what he called dangerous nationalist ideology", Reuters reports.
"Without borders there is no nation, there is no Republic, there is no civilisation," Mr Sarkozy told 10,000 supporters on Sunday. "We are not superior to others but we are different."
Mr Hollande took the moral high ground when he addressed some 22,000 Socialist voters at a simultaneous rally in Paris, saying he would not stoop to using such vote-garnering tactics.
"I want victory, but not at any price, not at the price of caricature and lies. I want to win over the men and women who are angry, a hundred times yes, but compromise myself? A thousand times no."
There was scant mention of the economy from either, despite widespread concern over sickly growth levels that are threatening deficit-cutting targets in Europe's No 2 economy.
Mr Hollande's tax-and-spend programme seeks to balance the budget in 2017, a year after Mr Sarkozy, who wants to trim labour costs to boost competitiveness. Analysts say that whoever wins, big austerity cuts will be needed in the months ahead.
The surprise score of National Front leader Marine Le Pen, who swept 17.9% of the presidential first round on 22 April to rank third behind Mr Hollande and Mr Sarkozy, has turned the runoff into a fight for her voters, many of whom say they will abstain.
Libyan fund report dismissed as Socialist ploy
Nicolas Sarkozy has dismissed a report on Sunday that former Libyan leader Muammar Gaddafi sought to fund his 2007 campaign as a ploy by his Socialist opponents.
The Mediapart website said it had uncovered a document from Libya's former secret services showing Colonel Gaddafi's government decided to finance Mr Sarkozy's run at the presidency when he was interior minister, Reuters reports.
Mr Sarkozy, whose government had played a key role in the deposing of Colonel Gaddafi last year, has repeatedly denied receiving any money from the former Libyan leader, who was captured and killed by the Libyan National Liberation Army last year.
He said Socialists were trying to distract attention from the public reappearance of former International Monetary Fund managing director Dominique Strauss-Kahn, who resigned in disgrace last year.
"Who led the coalition to topple Gaddafi? It was France!," Mr Sarkozy told Canal+ television. "Do you think that if Gaddafi had anything on me I would have tried to oust him?"
"It's a disgrace. It's a fabrication," Mr Sarkozy said, accusing the website of working in the service of the left.