Biden in New Hampshire

Then there was the matter of climate change. Mr. Biden repeatedly cited his initial legislative push on that issue from more than three decades ago. His goal was to highlight his long record of championing the environment, a critical issue to Democratic voters at a moment when Mr. Biden finds himself under fire from the left over how bold he is willing to be on climate. But the frequent references to remarks he made in 1987 — Mayor Pete Buttigieg of South Bend, Ind., a presidential opponent, was 5 years old that year — offered reminders of the stark generational divide in the sprawling Democratic field.