Political parties influence public policy through various mechanisms, including lobbying, advocacy, and party platforms. They mobilize voters to rally support for specific policies and candidates, shaping the political discourse. By proposing legislation and participating in government decision-making, they ensure that their policy agendas are reflected in governance. Additionally, parties may collaborate with interest groups to amplify their efforts and implement programs aligned with their ideological goals. Overall, their influence is significant in determining the direction and implementation of public policy.