French election: Macron and Le Pen to face off in live debate tonight The candidates will try to appeal to undecided voters.

 -- Centrist Emmanuel Macron and far-right leader Marine Le Pen will face off in a live, televised debate tonight, four days before the second round of the French presidential election.

Wednesday's debate is expected to last more than two hours as both candidates try to appeal to undecided voters.

Macron is ahead in the polls, but an estimated 18 percent of voters are still undecided.

In the first round on April 23, Macron, a 39-year-old former banker, won 24 percent of the votes, while Le Pen took 21.3 percent of the votes. People will return to the polls on Sunday to choose which of the two candidates, and their vastly different world views, they want for the future of their country. Here’s what you need to know ahead of the election.

Who are the two candidates?



The former investment banker has promoted both pro-business and socially liberal policies, giving him a centrist appeal that other candidates lacked. However, opponents have criticized him for being a political novice while pointing to unpopular measures he backed during his tenure in government. Among those measures was a law named after him that allowed businesses to open on Sundays and gave employers more negotiating power over workers.

Le Pen, 48, is an anti-European Union politician who has promised to dump the euro as France's currency if she is elected president. Many commentators have drawn parallels between Le Pen and Trump given the similarities in their views on free trade, NATO, and migration. But, unlike Trump, Le Pen comes from a family that has been on the French political scene for decades.

Her father, Jean-Marie Le Pen, ran for president five times and was the leader of the National Front party until 2011 when his daughter took over. Le Pen went on to distance herself from her father, who had made anti-Semitic remarks. She’s also attempted to recast the party as a serious anti-establishment political force, known more for its Euro-skeptic and anti-immigrant policies than for its historical reputation as xenophobic and racist.

Campaigning ends

Parliamentary elections



ABC News' Lora Moftah contributed to this report.