Les gauches de la gauche à l´épreuve des mutations des classes populaires. À travers l'étude des gauches de la gauche des années 2010-à savoir le PCF, le PG, le NPA et LO-, cette thèse s'emploie à prolonger et discuter les travaux portant sur le divorce de la gauche et des classes populaires. À la croisée de la sociologie des partis politiques et de la sociologie des classes populaires notre thèse se propose d'apporter un éclairage sur la manière dont les transformations ayant affecté les classes populaires depuis les années 1980 et les représentations dominantes qui en ont été véhiculées ont renouvelé les liens entre les gauches de la gauche et leur traditionnel groupe social de référence. Nous entendons repérer le caractère populaire des formations partisanes des gauches de la gauche en dépassant l'analyse des propriétés sociales du personnel politique et en nous arrêtant sur les grilles de lecture partisanes du monde social, le travail partisan de propagande et d´enrôlement et les normes régissant le militantisme. Postulant une déclinaison localisée des « cultures partisanes » selon les configurations sociales et partisanes, les liens qui unissent les gauches de la gauche des années 2010 et les mondes populaires ont été mis en lumière à l'issue d'une enquête de terrain menée dans quatre espaces locaux : Villejuif, Saint-Brieuc, Saint-Étienne et Nantes. L'exploration des « gauches de la gauche » des années 2010 donne à voir comment les mondes populaires persistent à être un enjeu problématique mais central pour une partie de la gauche partisane. Loin de n'être que des porte-parole rationnels autoproclamés des classes populaires, les gauches de la gauche sont porteuses de « cultures partisanes » imprégnées de populaire. Elle ne font pas que parler des dominés, elles s'adressent à eux sur un ton populaire. Elles peinent néanmoins à voir aboutir ou à pérenniser leurs idylles avec les classes populaires notamment avec les franges pluri-dominées de ce groupe social. L'insertion des gauches de la gauche, héritières d'un modèle d'investissement efficace de la classe ouvrière, dans des contextes populaires renouvelés et largement défaits (éclatés, réfractaires à l'unité, indisposés à se mobiliser) permet d'apporter un éclairage sur ce bilan contrasté. Resserrer la focale sur les militants « produits de socialisations multiformes » et donc inégalement sensibles au populaire permettra de compléter l'analyse de rencontres des collectifs partisans et des classes populaires inégalement inabouties. / The « Lefts of the Left » confronting lower classes. This PhD thesis is dedicated to the study of the Lefts of the Left Parties in the 2010s in France, namely PCF, PG, NPA and LO. It aims to extend and discuss the scientific research regarding the divorce between leftist parties and the lower classes. This research work is therefore rooted in political sociology and lower class studies. It sheds light upon how the transformations that affected the lower classes since the 1980s and its related representations have modified the connections between the Lefts of the Left and their traditional reference group. We intend to identify the lower classes-related component of the Lefts of the Left political parties, beyond a focus on social properties of the political staff. We rather pay attention to the political parties' interpretative frameworks of the social world, partisan propaganda and enlistment work, and militancy norms. In this view, the connections between the Lefts of the Left in the 2010s and the lower class, based on a research survey conducted in four local spaces: Villejuif, Saint-Brieuc, Saint-Etienne and Nantes, are to be underlined. Exploring “the Lefts of the Left” of the 2010s allows us to understand how the lower classes remain a problematic and central stake for a part of the left parties. The Lefts of the Left are not only rational self-proclaimed spokespersons for the lower classes, they also convey partisan cultures draining a lower classes-related component. They do not only speak about the dominated, they also try to speak to them with their words. However, they hardly succeed in formalizing and perpetuating this positive relationship, particularly regarding the pluri-dominated parts of the lower class. The Lefts of the Left inherited an effective model of promotion of the working class. The context in which these parties' political action takes place is a renewed context characterized by the division and unwillingness to mobilize of the lower classes, which seem to be now largely defeated and fragmented. Analyzing the Lefts of the Left's insertion in this context contributes to shed light upon this contrasted assessment. We shall then put the emphasis on political activists who are embedded in multiform socialization contexts, and therefore unequally sensitive to lower classes' stakes. In doing so, we shall complete this analysis of unequally unaccomplished meetings between partisan organizations and the lower classes.

In the submitted thesis the author focuses on the rising popularity of extremist political parties in the Czech Republic. The popularity growth of extremist political parties in the Czech Republic is proven by election results in recent years. Right-wing extremists{\crq} ``combat power{\crqq} growth is closely connected with the increasing number of their followers. Regional elections in 2008, in which the Labour Party achieved almost 29 thousand votes, which represents eight times more than the party had achieved in the previous elections in 2004, can be a proof of that. What is more, this party achieved 1.07% votes in the European Parliament elections and it surpassed the limit which is necessary for the state subsidy requisition. In the Theoretical Part the author deals with definitions of basic terms ``extreme{\crqq} and ``radical{\crqq}. Then he deals with the theoretical division of the political scene, from both the current point of view and the historical point of view, into the rights and the lefts. Then he attends to some terms which are closely associated with extremism, such as: nationalism, anti-Semitism and racism. In the Conclusion of the Theoretical Part the author focuses on the far rights and the far lefts. He pays attention to both the current representatives and to their predecessors of those extreme lines. In the Practical Part the author sets his targets and defines hypotheses and he also attends to the used research procedure there. The research was made via questionnaire investigations. Questions were focused on people{\crq}s opinions which are related to inadaptable citizens and extremism. There were also some questions which were focused on activities of those parties in the above mentioned fields, regarding the inadaptable citizens and extremism, which have their members in the Parliament of the Czech Republic. In the Practical part of the thesis the author also evaluates the observed results in light of respondents{\crq} achieved level of education. In the Discussion of the thesis the author compares the observed data with the knowledge of experts. He also focuses on divergent opinions of asked respondents, in connection with their achieved level of education. The thesis and the observed results could be used by general public interested in extremism in the Czech Republic. Besides, the thesis and the observed results could be used as a source of information to improve general knowledge about the scene of extremism and about the problems pertaining to the scene in the Czech Republic.