First, let's begin by a warning. The title is misleading, this is not the tale of Coluche's life. If you decide to watch the movie for this reason, you'll be disappointed.
However, the story is an interesting one. It is the depiction of a society at a certain time - beginning at the 80's in France, up to Miterrand's election.
And how Coluche decided, as a joke, to run for the presidential election, only to realize this may be more than a joke. We follow how the clown Coluche began to take this situation seriously and finds himself finally trapped between a polical world - which contains a ferocity he completely underestimated - and its ego - pushing him to believe he may be the savior awaited by the people he met. Of course, nothing is so simple, and Coluche was really touched by the people he met, rediscovering some of the injustices France was doing nothing about.
On that angle, it also was one of the necessary step in Coluche's life that lead him to create "Les restos du coeur", an association that still is essential in France for the poor.
Thus, we have a movie quite dark for a biopic about one of the best French comic ever, and showing some of Coluche dark sides.
Even if we have some of his trademark sketches recreated, the movie is not for fans of the comic figure.
Secondly, and that is the main problem, the movie in itself is told and edited in a disappointing way. Some scenes are unecessary, some are not working very well and the scenario in itself could have been better managed (clearer and simpler, less support characters)... Antoine de Caunes makes a quite bad job as a director and lacks creativity.
Fortunately, the acting of François-Xavier Demaison is great. Without imitating Coluche directly, he really is embodying him.
All in all, we have a not remarkable movie in its making, dealing with a strong story, almost tragic (the clown, suddenly serious, and trapped in a chain of event that will leave him at the verge of death, spiritually speaking) - and at the same time chronicle of this period of time, and supported by a great acting of the main role.