Perhaps more consequentially, Mr. Sanders told reporters on Tuesday that he would be changing the “nature” of his campaign by doing fewer events. On Wednesday, he said he had misspoken.

Mr. Sanders acknowledged in an NBC interview that he had received the heart attack diagnosis last Tuesday night, three days before his campaign disclosed it.

As our colleagues Sydney Ember and Jonathan Martin reported, Mr. Sanders’s wife, Jane, his most trusted adviser, has helped shape the campaign’s response.

Republicans are attacking Warren

Senator Elizabeth Warren of Massachusetts often tells voters that after she became “visibly pregnant” at the end of her first year as a public-school teacher, the principal wished her luck and hired someone else to replace her.

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This week, a conservative news site and other outlets challenged her account, citing a 2007 interview with Ms. Warren and minutes from a school board meeting — and Ms. Warren pushed back in a unique way. Rather than just restating the truth of her account (though she has done that as well), she called on women to share their own stories of pregnancy discrimination, which remains widespread.

The candidates talked L.G.B.T.Q. rights

CNN and the Human Rights Campaign hosted the latest subject-based forum of the presidential race on Thursday, focused on gay, lesbian, bisexual and transgender issues. Protesters interrupted the event at several points to call attention to the murders of black transgender women, and the candidates seemed to welcome the reminder.

You can read about the forum here.

Before the event, Ms. Warren, Mayor Pete Buttigieg of South Bend, Ind., and Senator Kamala Harris of California released plans on L.G.B.T.Q. equality. All three said they would fight to pass the Equality Act and ban conversion therapy as president.