Francois Hollande, the Socialist candidate for president of France, bested President Nicolas Sarkozy on Sunday in the first round of voting, according to the Interior Ministry, and headed into a May 6 runoff election favored to become the country’s next chief executive.

Hollande won 28.6 percent to Sarkozy’s 27.1 percent, the Interior Ministry said, with 99 percent of votes counted, according to the Associated Press, giving the Socialist contender momentum that commentators said will be hard to stop. Placing third was Marine Le Pen of the far-right National Front, with up to 18 percent. The rest of the vote was spread among Jean-Luc Melenchon of the Leftist Front, with 11.1 percent, and six other minor candidates.

“This is an act of confidence in the project I have presented to put the country back in order,” a smiling Hollande said in a post-vote statement.

The conservative Sarkozy, in office since 2007, has led France through the economic and financial crisis that has been battering Europe for four years, lowering living standards for millions. Like other European leaders, he saw his popularity decline as the crisis unfurled under his presidency and, partly as a result, has trailed Hollande consistently, with about 45 percent support vs. Hollande’s 55 percent, in polls measuring second-round preferences.

In a brief speech after the results became known, Sarkozy called the coming two weeks a “crucial confrontation” and challenged Hollande to meet him for three televised debates before May 6. Hollande has rejected suggestions that the traditional single debate be expanded to two.

In addition to the financial crisis, Sarkozy, 57, also is disadvantaged, polling experts said, by his rough-edged personality and his attraction to the high life, both of which they said probably turned off a number of undecided voters who might otherwise have rallied to his candidacy for a second five-year term. Despite his prowess as a campaigner, they said, he faces an uphill battle over the next two weeks and is likely to count heavily on a televised face-to-face debate — or debates.

Despite predictions of a low turnout and complaints that candidates were skipping over the real problems of the French people, up to 80 percent of registered voters cast ballots, the polls estimated.

The relatively strong showing by Le Pen, who took over recently from her often obstreperous father, showed the extent of discontent at the increasingly visible presence of Muslim and other immigrants in France’s Christian-rooted society. It also reflected anger among some working-class French people who feel they have been left in the lurch by France’s traditional political parties during the crisis, specialists said.

The same sentiments helped explain Melenchon’s showing, a response to far-left proposals for taxing the rich at 100 percent, taking over banks and raising the minimum wage. Having lodged their protest votes in the first round, many of his backers are likely to swing to Hollande in the second round, polling experts said, and Melenchon immediately urged them to do so.

If Sarkozy is to win the second round, they said, he will have to win back a large number of the National Front voters, about 40 percent of whom voted for him in the second round in 2007 and provided his margin of victory. But some are likely to abstain, they said, and still others could tip to Hollande as someone more likely to heed their economic concerns.

Hollande, a moderate social democrat, has promised to hire more teachers and stimulate employment through economic growth, seeking to set himself apart from Sarkozy’s austerity measures. At the same time, he has made it clear he would have to deal first with the staggering deficits that France has rolled up over the years to finance its social protection programs.

Hollande, 57, has said he will demand changes to the austerity pact that was reached by European Union countries in December and that bound them to limit their deficits and public debt levels — in effect obliging them to impose austerity policies. He has said that the pact should also contain an effort to kick-start economic growth because that is the only thing that can lower unemployment and increase the flow of tax revenue into empty government coffers.