Reason is to give a sanitized version of the democratic party

Using their political positions, some representatives may feel constrained to only speak up to a point, limiting their activism to certain votes or statements. This behavior results in a perception among working people that the Democratic Party is more aligned with their interests than it truly is. The representatives, consciously or unconsciously, serve to provide a sanitized portrayal of the party, which can mislead the public into believing that existing within the party framework offers genuine advocacy for their issues. Thus, the actual role fulfilled is one that may pacify the working class rather than instigate the necessary change.