It was a night of former presidents and would-be presidents, and the prime-time debut of Gov. Tim Walz, who was cheered by members of the high school football team he once coached. Democrats on Day 3 of their national convention also celebrated Minnesota, the home state of Mr. Walz, with a special tribute to the artist once known as Prince, and an appearance by Senator Amy Klobuchar.

Still, the night proved that celebrity still matters in politics and beyond. Here are some highlights:

Throughout the night, Democrats channeled their inner Ned Flanders, the “Simpsons” character known as the most neighborly neighbor in Springfield.

Speaker after speaker stressed that, even as they thrashed Donald J. Trump inside the convention hall, they did not view his followers as their enemies.

“That family down the road — they may not think like you do, they may not pray like you do, they may not love like you do, but they are your neighbors,” Mr. Walz said in his speech accepting the Democrats’ vice-presidential nomination. “You look out for them, and they look out for you.”

And Oprah Winfrey said before that: “We are not so different from our neighbors — when a house is on fire, we do not ask about the homeowner’s race or religion, we do not wonder who their partner is or how they voted.”