In this study, we analyzed the factors that intensified affective polarization among voters during the 2022 South Korean presidential election. We also examined this polarization's effect on their political attitudes, including their satisfaction with democracy, perception of the fairness of elections, and trust in political institutions. We found that the greater the perceived ideological differences between the two parties the People Power Party (PPP) and the Democratic Party ― (DP)―and the more extreme the voter's ideology, the more affective polarization increased. We also found that affective polarization intensified with increasing ideological extremity among all age cohorts except those in their forties. Finally, in contrast to DP supporters, PPP supporters' political attitudes became more negative as their affective polarization increased because the opposing party, the DP, was the governing party. This suggests that affective polarization may polarize support for democratic norms and trust in the political institutions that underpin democracy, depending on one's partisan allegiances.