ABSTRACT
This research focused on a political process, the study of which has been routinely neglected by political scientists: the formal or informal co-option of ERPs by mainstream parties. This political process was frequently associated with immigration policy and has been identified in the past in the UK and France. Co-option was interpreted as a bi-dimensional political phenomenon: primarily as a demonstration of a challenger party's impact on a political system, and second, as a strategic option employed by mainstream parties to neutralise the challenger party. Consequently, the research sought to identify the ERPs' impact on immigration politics and policy and to understand the latter political processes by assessing the relevance of the proposed hypotheses (Table 2.1).
