After months of restraint, former Vice President Joseph R. Biden Jr. toughened his position and called for Mr. Trump’s impeachment for the first time last week. (Mr. Trump is facing an impeachment inquiry in the first place because of his request to the Ukrainian government that it look into what Mr. Biden did with the country’s officials when his son, Hunter Biden, was working for a gas company there.)

At the same time, others like Ms. Gabbard, have been careful to endorse only the impeachment inquiry and not necessarily impeachment itself.

Below is a partial transcript of the exchange on impeachment at Tuesday night’s Democratic debate:

WARREN: Sometimes there are issues that are bigger than politics. I think that’s the case with this impeachment inquiry. When I made the decision to run for president, I certainly didn’t think it was going to be about impeachment. But when the Mueller report came out, I read it, all 442 pages. And when I got to the end, I realized that Mueller had shown ... that this president had obstructed justice and done it repeatedly. And so at that moment, I called for opening an impeachment inquiry. Now, that didn’t happen and look what happened as a result. Donald Trump broke the law again in the summer, broke it again this fall.

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You know, we took a constitutional oath, and that is that no one is above the law, and that includes the President of the United States. Impeachment is the way that we establish that this man will not be permitted to break the law over and over without consequences. This is about Donald Trump. But understand, it’s about the next president and the next president and the next president and the future of this country. The impeachment must go forward.

ANDERSON COOPER: Thank you, Senator Warren. You’re all going to get in on this, by the way. Senator Sanders, do Democrats have any choice but to impeach? Please respond.