PARIS — Leftist firebrand Arnaud Montebourg is basing his bid for the French presidency on a simple bet: that François Hollande is so dismally weak in opinion polls a strong left-wing candidate could easily snuff out his chances of winning re-election next May.

"I ask him [Hollande] to think about his decision, to consider the facts, to take into account his historical and unprecedented weakness in the eyes of the French," Montebourg said Sunday in a speech announcing his candidacy. "Our failure in front of France has everything to do with being resigned to our fate."

It's an argument that echoes the logic behind Bernie Sanders' surprisingly successful primary campaign in the United States.

Like the Vermont senator, Montebourg, a former industry minister, sees a strain of resentment for the mainstream Left's candidate that, if anything, is more widespread in France, for Hollande, than it was in the United States, for Hillary Clinton.

But even if the diagnosis is similar on both sides of the Atlantic, the political landscapes are very different. In the United States, Sanders enjoyed sublime isolation on a left fringe of the Democratic Party empty of serious competitors, leaving him free to fight the establishment on his own. In France, Montebourg faces the opposite situation: a far-left lane already choked with eager Bernie clones, all of whom are desperate to take down Hollande.

The leftmost lane is now so clogged it will be difficult for Montebourg, or anyone, to break out ahead of Hollande.

From Jean-Luc Mélenchon, a cantankerous far-left MEP who calls Germany a "poison" for Europe; to Benoît Hamon, a rising Socialist scrapper and wealth inequality crusader; to Gérard Filoche, an über-gruff ex-Trotskyite who has carved out a niche as Hollande's most vicious left-wing critic; and others — the leftmost lane is now so clogged it will be difficult for Montebourg, or anyone, to break out ahead of Hollande.

Four months before Socialists vote to pick their presidential candidate in a primary, here is a close-up view of France's Sanders clones along with how they score on a scale of Bernie-ness, from 1 to 10. Each candidate carries his or her own banner of leftism. All want to feed off the carcass of Hollande's cautious, establishment socialism.

Arnaud Montebourg

Tall and tousle-haired, with a florid speaking style and rebellious streak, Montebourg exploded onto the political scene in 2012 when his anti-globalist current won 17 percent of the vote during a Socialist primary. His success forced Hollande to give him a cabinet seat, where he immediately created trouble for the president: As industry minister, Montebourg insulted foreign business tycoons (famously telling Arcelor-Mittal CEO Lakshmi Mittal he could "get out of France") and intervened willy-nilly in private business, single-handedly reviving France's reputation as a statist nightmare for foreign investors.

His run ended in 2014 after he was caught making a bawdy joke at Hollande's expense, and ever since Montebourg has been anxiously toeing the sidelines, casting himself as the chief of Socialist rebel backbenchers as he prepared a comeback to politics.

Now that he is officially back, things are looking tricky for Montebourg. In his Sunday speech, he ran through a litany of familiar campaign themes: Hollande's legacy of hopelessness; Germany's unfair domination of fiscal and monetary policy in the EU; the need to reassert France's voice in the bloc; and kickstarting France's industrial sector via a protectionist "Made in France" trade and investment policy.

But what he left out was arguably the key practical consideration: exactly how he will run. If Montebourg signs up as a candidate in the Socialist primary next January, he faces a serious challenge from Hamon, his former sidekick in government who also styles himself as the chief of rebels, with both standing a good chance of getting knocked out by Hollande (the president is expected to run but has not declared his candidacy).

If Montebourg runs as an independent, with or without Hollande in the race, he has a slightly better chance of making it to the run-off round against a right-wing challenger, possibly National Front chief Marine Le Pen. But the second option includes several caveats. As an independent, Montebourg would be up against Mélenchon, whose anti-German agenda is remarkably similar to his own. Having both in the race could well split the left-wing vote, bury Hollande and any other left-winger, and all but guarantee a Right-only final battle.

Asked about his choice Monday on France 2, Montebourg said: "I have no decision to take, because we don't know exactly how the primary will be organized." That excuse will hold for a while longer, with candidates facing a December 15 deadline to join the primary. Until then, Montebourg will play the clock, probe his rivals' weaknesses and hope for the best — that Hollande drops out of his own volition.

Bernie-ness score: 6 out of 10

Montebourg is a protectionist, a major critic of international finance and a big advocate of direct democracy. But he splits with Sanders on big corporations, which Montebourg defends fiercely as part of a statist, top-down vision of how the French economy should be run. Montebourg also cultivates ties with business leaders, like investment banker Matthieu Pigasse, that Sanders might denounce as corruption.

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Jean-Luc Mélenchon

Twelve years older than Montebourg, Mélenchon at times seems to have been teleported from another era. His stump-thumping speeches are unapologetically Marxist in the way they embrace class struggle as a fact of life, and Mélenchon delivers them as if he were haranguing a crowd of striking miners in 1930s France.

Despite his gritty style, or perhaps because of it, Mélenchon has successfully positioned himself as France's dominant hard-left politician at a time when Hollande's Socialists are struggling to decide between their Marxist roots and a shift to social democracy. In the first round of a 2012 presidential election, Mélenchon won 11.1 percent of the vote, before rallying behind Hollande and ultimately handing him a victory.

Over the past four years Mélenchon has refashioned himself as a major scourge of Hollande, as well as France's most outspoken critic of Germany. His book "Bismarck's Herring," a nakedly anti-German screed, sold more than 37,000 copies, making it one of the year's best-selling political titles. In it, Mélenchon argues that Germany's pursuit of economic self-interest is a "poison" that has infected the rest of Europe, relegating France to the status of a second-tier nation.

But there is competition on the anti-German market. Montebourg may be less fiery, but his critique of the European Central Bank is just as wary of German influence as Mélenchon's attacks on the country's export model. Last year, Montebourg touted a bromance with former Greek finance minister Yanis Varoufakis, whose main point of convergence was resentment for austerity policies originating in Berlin.

The overlap might explain why Montebourg is hesitating on how to run. Mélenchon, who is polling above Hollande, is set on challenging the president outside the Socialist party by running as an independent far-left candidate. If Montebourg chooses the same tactic, the two men will face off in a destructive battle of leftists that would have the effect of eliminating them both, with the former stronger among younger voters and Mélenchon heavily supported by trade unionists.

Bernie-ness score: 4

If Sanders shocked some Americans by calling himself a socialist, the question for Mélenchon is: Are you a communist? Formerly a member of the Socialist party, Mélenchon shares Sanders' basic software when it comes to class struggle and income inequality. And he has explicitly tried to model some of his social media tactics to bolster his own following. But Mélenchon lacks the Vermont senator's progressive vibe and anti-authoritarian appeal.

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Benoît Hamon

Once upon a time, this fresh-faced 49-year-old was Montebourg's sidekick in government. Residing two floors below the industry minister at the finance ministry, Hamon complemented his elder's "Made in France" ethos with hip advocacy for collaborative economics, as secretary of state for the social economy. In 2014, having been promoted to education minister, he followed Montebourg out of Hollande's government on a wave of disgust for its shift to supply-side economic policies — and has lived on as a rebel backbencher ever since, leading votes against the majority.

As such, Hamon became a competitor for Montebourg, and their friendship did not survive. In fact, it's turned into a low-key sniping war ever since Hamon said he would run in the Socialist primary, and Montebourg's team dismissed his candidacy as nothing to be afraid of. "Benoit will create a buzz for 48 hours; Arnaud will create a buzz for 48 weeks," a Montebourg backer whispered to the Canard Enchainé. That prompted Hamon to invite Montebourg to join his campaign as a supporter.

In terms of voter recognition Montebourg is undoubtedly the bigger fish, but Hamon has an edge: As an MP with time on his hands, he's worked much harder to win support from other elected officials, and claims to have the backing of 22 rebel backbenchers versus just nine for Montebourg. The latter's lieutenants are not impressed. At some point, they argue, Hamon should see the light and rally behind his political big brother.

Bernie-ness score: 8

Heavily focused on wealth inequality, wary of big banks and corporations, obsessed with citizen initiatives and alternative economic models, Hamon falls short of a perfect Bernie score only in one area: the enthusiasm he generates among voters.

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Gérard Filoche

Burly and gruff to the point of caricature, Filoche is often a punchline of jokes on the outdatedness of French leftist politics. The former labor inspector and militant communist joined the Socialist party late in life, but lost nothing of his disdain for establishment politicians. Announcing his intention to run in the Socialist primary, he dismissed Hollande as having zero chance of winning the presidency given the depth of anger against him among traditional Green party and left-wing voters. "Even a goat would win against Hollande," he told Le Point magazine in June.

But Filoche is not to be dismissed. At 70, he is more plain-spoken and frank than his younger rivals, and there is no ambiguity about his political positioning. He is staunchly pro-union, anti-establishment and anti-capitalist. As such, he shares many traits with Sanders in the U.S. and Jeremy Corbyn of the Labour Party in Britain. Both men were dismissed as laughing stocks before they rose to prominence in their parties.

Bernie-ness score: 8.5

Filoche has in common with Sanders his white-hair, commitment to the working man and immaculate record of left-wing activism. Another shared trait: the fact that neither man has participated in a government or held executive office.

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Marie-Noëlle Lienemann

Less well known than the other candidates, Lienemann is a career Socialist who has occupied a range of positions in government, from housing minister to deputy mayor and, currently, senator. Her name is sometimes cited derisively as proving that the Socialist primary consists of various "nobodies" sent to compete against Hollande and make him look good.

But it would be foolish to overlook Lienemann, who is one of the few women in the race, more qualified and tested in office than Mélenchon or Filoche, and largely in tune with the anti-Hollande feeling in the party. A backbencher rebel, she will run against Hollande by arguing that he betrayed leftist values and the voters who put him in office. Explaining her choice to run in the primary, she cited ... guess who? "Everywhere in the world, globalization is starting to be rejected by the people," she told Le Monde in March. "Even in the United States. On the Right, it's the populism of Donald Trump; on the Left, it's the search for a new path with Bernie Sanders."

Bernie-ness score: 4

Lienemann may feel the Bern, but her career in government means that she lacks the ideological purity of the former Democratic candidate.