French President Nicolas Sarkozy and his wife Carla Bruni voted Sunday in the first round of France's presidential election.

Mr. Sarkozy's main opponent, Socialist Francois Hollande cast his vote earlier in the day.

Opinion polls before the election indicated that Mr. Sarkozy was trailing Mr. Hollande by several points.

Pollsters say Marine Le Pen on the far right and Jean-Luc Melenchon on the far left are expected to place third and fourth, respectively.

Sunday's vote will whittle down the field from 10 to two, and Mr. Sarkozy and Mr. Hollande are expected to face each other head-to-head in a May 6 runoff to determine who will run France.

Under French law, the media are barred from announcing early or partial results before the polling stations close Sunday evening .

On Friday, the conservative Mr. Sarkozy apologized for his actions in the early days of his five-year term. He said his mistake was “not understanding the symbolic dimension of the president's role.” However, he defended his role in curbing French spending to help resolve the European governmental debt crisis. He said France would face more difficulties like debt-ridden Spain if it changes course.

Mr. Hollande is a veteran politician who headed the Socialist Party for several years. But he has never held a top government post.

During the campaign, Mr. Hollande blamed Mr. Sarkozy for France's unemployment rate of nearly 10 percent and called for sweeping changes to improve France's public finances.

President Sarkozy has said in interviews that the rule barring the announcement of early results is outdated. The law does not affect foreign-based media and the information is expected to be widely available on Twitter and Facebook well before official results are announced Sunday evening.