Transcript for What's at stake in the French presidential election

Next to that presidential election in France, capturing much of the world's attention. Violent protests breaking out the day before they head to the polls. As Alex Marquardt reports, it's one of the most contentious contests in memory. With one of the leading candidates being compared to president trump. Reporter: Tonight, France bracing for a contentious election. Divisions on full display on is the streets of Paris today as trade yuanists clashed with police. The effects of the vote will be felt around the world. An election even more uncertain after Thursday's attack on Thursday that left one policeman dead. Trump telling the ap, the attack will probably help far-right candidate marina LE pen, as she promises to pull France out of the eu and vows to crack down on immigration and islamic extremism. Russian president Vladimir Putin showing his support for LE pen in a surprise meeting in March. But she faces a tough battle, neck and neck with three other candidates for a spot in the second round. Each trying to convince their voters her radical proposal isn't the way to go. One of them Emmanuel macron, 37-year-old upstart. Who has never held an elected office. Other voters may be looking for a steady hand in these uncertain times and turn to embattled former prime minister. The top two candidates tomorrow will move on to the final round due to be held in two weeks. This election is wide open. What's clear, its ramifications could upset the order here in Europe and beyond. Tom. And that's why the world is watching. All right, Alex, thanks very much.

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