- President Nicolas Sarkozy and challenger Francois Hollande compete in a runoff
- If Sarkozy loses, he will be one of a series of European leaders swept from office
- France is a key player in plans to lead the eurozone out of its debt crisis
- Hollande appeals for unity as the incumbent urges the nation to support him
Paris (CNN) -- France votes Sunday in a presidential runoff dominated by economic concerns as incumbent Nicolas Sarkozy battles a wave of discontent over his inability to rein in unemployment.
The runoff pits the incumbent against Francois Hollande, who if elected would be the nation's first left-wing president since Francois Mitterrand left office in 1995.
Sarkozy has defended his economic record despite low growth and unemployment at about 10%, saying the impact of Europe's debt crisis could have been far worse.
France is a key player in plans to lead the eurozone out of its debt crisis, making the election vital to the region.
If Sarkozy is defeated, he will be one of a series of European leaders swept from office during the eurozone economic crisis, including the Greek and Italian prime ministers.
Concerns over the economy, unemployment and immigration have been at the forefront of the French election.
In his final address Friday, Sarkozy, of the center-right UMP party, picked up on the debate over immigration as he appealed for the nation's support.
"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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French presidential rivals trade insults "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.
The two rivals traded insults last 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.
Both candidates reached out to France's undecided voters since the first-round vote on April 22 left them the only two standing.
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.
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.
France's vote is the same day as the Greek parliamentary election, where the austerity crisis gripping the nation is expected to be at the forefront.
CNN's Saskya Vandoorne and Stephanie Halasz contributed to this report.
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