The survey showed that 41 percent of partisans agreed that simply winning elections is more important to them than policy or ideological goals, while just 35 percent agreed that policy is a more important motivator for them to participate in politics. Only 24 percent valued both equally or expressed no opinion.

This is from 2015, but it explains so much. If anything, 35% seems like a bit much for people who are primarily motivated by policy. Maybe it’s gotten worse since then.