Affective polarization has been posited as a key explanation for citizens’ tolerance towards democratic backsliding. Our study adopts the opposite perspective, theorizing partisan-based affective divides not as a cause of backsliding, but its consequence. We contend that backsliding crystallizes an affective dislike among opposition supporters towards the governing party and its supporters that stems from a divide over democracy itself. To explore this argument, we leverage original survey data collected in Hungary and Poland. Our results point to a government-opposition divide in partisan affect and show how liberal democratic attitudes especially among opposition party supporters play into this dynamic. We submit that where backsliding persists over a longer period, this process can shift even multi-party systems towards increasing bipolarity along what we term a ‘democratic divide.’ Ultimately, our findings suggest that affective polarization may play a positive role in backsliding contexts by uniting the opposition around the defense of democracy.