What’s Next for the Harris Campaign

President Biden endorsed Vice President Kamala Harris to lead the presidential ticket after ending his re-election campaign on Sunday, raising the chance that she could be the first Black woman to be president of the United States.

Ms. Harris in many ways has been preparing for this moment for the past year as she emerged as one of the Biden campaign’s more aggressive voices on abortion rights and attacks on former President Donald J. Trump. Mr. Biden spoke to Ms. Harris on Sunday morning before he posted a letter online informing the world that he would be stepping down as the Democratic nominee.

In another post less than a half-hour later, he endorsed Ms. Harris, who quickly issued a statement saying she intended to “earn and win this nomination.”

But as the details of the nominating process remain unclear, there are many questions Ms. Harris and her team will face in the days ahead.

Ms. Harris will now need to take over the vast infrastructure of Mr. Biden’s campaign, which has roughly 1,300 staff members and dozens of offices around the nation. There are signs that is already happening.

On a call with the Biden campaign staff on Sunday, Jen O’Malley Dillon, the Biden campaign chairwoman, and Julie Chavez Rodriguez, the Biden campaign manager, informed the staff members that they were all now working for Harris for President, according to two people who listened to the call. “We’re all going to do it the same,” Ms. Chavez Rodriguez said.