Mainstream ideological and public opinion is the soul of social progress and the main driving force for promoting social development. It can guide social trends, unite people’s hearts, promote consensus, and provide solid ideological support for social stability and harmonious development. As an important measure to consolidate and strengthen mainstream ideological and public opinion, “Party controlled media data” is a requirement of the new era and new journey to adhere to the guiding position of Marxism in the field of ideology. The “Party controlled media data” has political value, public value, public welfare value, and economic value for the consolidation and growth of mainstream ideological and public opinion. It is conducive to enhancing the dissemination power of mainstream ideological and public opinion, enhancing its guidance power, expanding its influence, and building its credibility. The concept of “Party controlled media data” is a newly solved topic, which is a concept with contemporary characteristics compared to “Party controlled media”. It is an extension of the connotation of “Party controlled media” in the digital civilization era. The “Party controlled media data” provides technological support and innovative communication methods for the consolidation and growth of mainstream ideological and public opinion. However, due to the continuous iteration and optimization process of “Party controlled media data”, the consolidation and growth of mainstream ideological and public opinion also faces some deep-seated practical challenges, mainly focusing on the problems in its own construction and the challenge of data ideology faced by mainstream ideological public opinion. The consolidation and strengthening of mainstream ideology and public opinion through the Party’s management of media data is not only a trend of the times, but also a choice for the Party’s long-term governance. In practice, there should be a top-level design of management orientation and management concepts, as well as specific path arrangements for talent management, rule management, and technology management.