With increasing polarization in the U.S., political discussions between friends and family members from different parties can be fraught. But how do these political factors influence people’s love lives? We know little about how often people in romantic relationships have political disagreements and whether political differences affect couples’ happiness, or whether some couples navigate these differences better than others. To address these questions, we surveyed over 4,000 people in the U.S., including more than 500 couples. Political differences in our large sample of couples were relatively rare: Only about 23% of couples belonged to different parties, and fewer than 8%...