France gears up for presidential runoff

Paris (CNN) -- France votes Sunday in a presidential runoff pitting incumbent Nicolas Sarkozy against Francois Hollande in an election dominated by economy, unemployment and immigration concerns.

Campaigning concluded at midnight Friday.

In the first round of voting, nearly a fifth of voters backed far-right National Front leader Marine Le Pen -- who wants to limit the number of immigrants entering France -- leading both candidates to reach out to her supporters.

In his final address Friday in Paris, Sarkozy, of the center-right UMP party, picked up on the debate over immigration as he appealed for the support of the whole nation.

"I've always said that France needs to remain an open and profoundly humanistic country, but there is a reality that is that we have welcomed more people in France than we can manage," he said.

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"I'm not speaking to the right, the left or the center, this is a presidential election. I am president of France. I must speak to the French, no matter who they are."

Hollande, of the center-left Socialist party, also appealed for unity at his final rally in Perigueux, southwestern France.

"If so many of you have come today, it's because you know that Sunday you will make an important choice for our future. If there are so many of you, it's because you want to express your worry, and you have expressed this in multiple ways in the first round of the elections," he said.

"There have been votes in this very neighborhood that went to the National Front. We have the responsibility to unite, to reconcile. I don't want a France that is divided."

The two rivals traded insults earlier this week in the only televised head-to-head debate of the campaign.

Sarkozy labeled Hollande a liar and a "little slanderer" while Hollande accused the president of shirking his responsibilities, cronyism and favoring the privileged over France's poor.

Sarkozy has defended his economic record, despite low growth and unemployment at close to 10%, saying the impact of Europe's debt crisis could have been far worse.

Both candidates have been working hard to reach out to France's undecided voters in the two weeks since the first-round vote on April 22 left them the only two still in the race.

Centrist Francois Bayrou, who took 9% of the first round vote, delivered a boost to Hollande's campaign Thursday when he said he would vote for the Socialist, and urged his supporters to vote according to their conscience.

Le Pen, who said she would cast a blank vote on Sunday, declined to endorse either candidate.

Under French election law, no opinion polls or partial results can be published before the polls close at 8 p.m. local time (2 p.m. ET) Sunday.

If elected, Hollande would be France's first left-wing president since Francois Mitterrand left office in 1995. Sarkozy has been president since 2007.

CNN's Saskya Vandoorne and Stephanie Halasz contributed to this report.