Here’s how we analyzed the Democratic debate.

Hillary Clinton and Senator Bernie Sanders of Vermont faced off yet again Sunday night, after a weekend of voting where both Democrats notched wins. Mr. Sanders won the Maine Democratic caucuses, according to The Associated Press. The debate, hosted by CNN, took place in Flint, Mich., a town facing a drinking water crisis, in a state where voters head to the polls on Tuesday that will prove a crucial test for both candidates.

• Anderson Cooper, the debate moderator, kicked off the night by explaining why CNN had chosen to stage its latest debate in Flint, Mich. The city is “in crisis,” he said, and the water “is toxic.”

• Both Mr. Sanders and Mrs. Clinton also paid homage to Flint in their minute-long opening statements, calling for the state’s governor, Rick Snyder, to resign. Mr. Sanders called the situation in Flint “a dereliction of duty,” and Mrs. Clinton said she planned to “continue to shine a very bright spotlight on what has happened in this city.”

• Mrs. Clinton declined to say if the head of the Environmental Protection Agency should be fired, saying she didn’t know how high up the chain the problem went. But both she and Mr. Sanders said whoever was responsible for the crisis should absolutely be relieved of their job.