Donald Trump was never supposed to win the US election and even Brexit campaigners were surprised when Britain voted to leave the European Union, so the prospect of National Front candidate Marine Le Pen becoming French president does not seem as unlikely as it once did.

Her main rival, Francois Fillon, has found himself embroiled by a scandal over payments made to his wife and now moderate voices on both left and right are looking to Emmanuel Macron, a centrist, to mount a serious opposition to Le Pen. Meanwhile, Benoit Hamon has been rallying many behind his Jeremy Corbyn-esque brand of left wing, anti-establishment politics.

In this week's In the Field, senior foreign reporter Callum Paton and France-based journalist Colin Randall, help to make sense of the most unusual French election since the last time a Le Pen came close to winning the French presidency, in 2002. Back then, it was Marine Le Pen's now-estranged father Jean-Marie Le Pen who made it through to the second round in the presidential race.

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