PERSONALIZED POLITICS IN THE DIGITAL AGE: HOW MEDIA EXPOSURE AND SOCIAL MEDIA MICRO TARGETING IMPACT PUBLIC AGENDA DIVERSITY AND WIDEN PARTISAN POLARIZATION IN U.S. PRESIDENTIAL ELECTIONS (2012-24)

Author

• Kazi Mehedi Mehedi Hasan, Southern Illinois University CarbondaleFollow

Date of Award

5-1-2026

Degree Name

Doctor of Philosophy

Department

Mass Communication and Media Arts

First Advisor

Karan, Kavita

Abstract

This study examines how evolving media environments and election campaign strategies have shaped political polarization and public agenda diversity in the United States from 2012 to 2024. As social media has overtaken traditional news as a primary source of political information, concerns have grown about selective exposure, misinformation, and strategic uses of the media. Using a mixed-method approach, the study analyzes nationally representative American National Election Study (ANES, 2026) survey data across four presidential elections alongside a qualitative case study of U.S. presidential campaigns. Findings indicate that campaigns increasingly adopted personalized political strategies through social media microtargeting, prioritizing emotionally charged issues to mobilize partisan supporters rather than persuade undecided voters. Social media is a stronger predictor of both ideological and affective polarization than legacy media, reinforcing partisan echo chambers and widening political distance between Democrats and Republicans. The prioritization of emotional issues by both campaigns amplified polarized beliefs on immigration, crime, and taxation. Although public agenda diversity fluctuated across election cycles, it showed no significant relationship with affective polarization, suggesting that polarization is driven less by issue diversity than by partisan framing, emotional mobilization, and selective media exposure in contemporary digital political communication.