It was a busy week in the Democratic presidential campaign, with a flood of new policies and, of course, another debate.

Let’s get right to it.

A surprisingly subdued debate

There weren’t a lot of sparks in this week’s debate, the fifth of the Democratic primary. But in the absence of a clear front-runner, several lower-polling candidates were able to break through — at least for one news cycle.

Senators Kamala Harris of California, Amy Klobuchar of Minnesota and Cory Booker of New Jersey all had strong nights. So did Mayor Pete Buttigieg of South Bend, Ind., who did not face nearly as many attacks as expected in his first appearance since he shot to the top of the field in Iowa.

Good news and bad news for Buttigieg

Mr. Buttigieg has had a remarkable rise in Iowa, rocketing from 9 percent (fourth place) in a CNN/Des Moines Register poll in September to 25 percent (first place) in one released last weekend. Between that and a Monmouth University poll four days earlier also showing him in first place, it is clear that Mr. Buttigieg has become a serious contender there.