French election: Macron and Le Pen to face off in live debate tonight

The candidates will try to appeal to undecided voters.

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.

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.

Campaigning ends

Parliamentary elections

ABC News' Lora Moftah contributed to this report.