While Biden dropped out of the race, he endorsed his Vice President Kamala Harris to replace him.

President Joe Biden announced on Sunday he will step aside and not run for re-election. Biden, embattled since a disastrous debate performance roughly a month ago that called into question his mental fitness, said he intends to fulfill the rest of his term.

In a statement on social media, Biden said it was “the greatest honor of [his] life” to be President, but that it was “in the best interest” of the Democratic Party and the nation to no longer run for re-election. In a follow-up post on X, Biden endorsed his Vice President Kamala Harris to replace him. Yet Harris has recently polled equally as poorly against Trump as Biden has.

Biden’s announcement came just a few hours after the latest polling in Michigan was released. It showed Trump’s lead over Biden widening in the crucial swing state.

For her part, Harris recently spoke to major donors in a conference call in an attempt to calm nerves. One person on the call said, “it was a total failure” while others said it was “mismanaged” and “rushed.”

Earlier in the day, reporting surfaced of Biden’s displeasure with former President Barack Obama after Obama was alleged to discourage Biden from running in 2016. The same displeasure has carried on into 2024, in which Biden believed Obama and his allies were trying to force him out.

Before Biden’s announcement, West Virginia Sen. Joe Manchin was the latest of dozens of Democratic lawmakers to call for Biden to step aside. Earlier in the weekend, Ohio Senator Sherrod Brown, who is engaged in a tough reelection battle against Republican candidate Bernie Moreno, also called for Biden to end his reelection bid.

Until Sunday, Biden remained defiant and pledged to charge forward. In a Zoom call with moderate Democratic House members a week ago, Biden got angry with Rep. Jason Crow when Crow told Biden his message on foreign policy victories were not breaking through with voters. Earlier, Biden told NBC’s Lester Holt his “mental acuity has been pretty damn good.”

The question now is who replaces Biden at the top of the ticket and how that happens. Aside from Harris, other names being floated are Pennsylvania Gov. Josh Shapiro, Michigan Gov. Gretchen Whitmer, and Kentucky Gov. Andy Beshear. Vice President Harris not only has Biden’s endorsement, but the conventional wisdom among Democratic operatives has Harris as the likely nominee.

It’s unclear exactly what the process for choosing a nominee will be now that the candidate with the most pledged is out of the race. On the first nominating ballot at the DNC, only pledged delegates are allowed to vote. If a majority is not reached, nearly 740 “superdelegates”–Democratic elected officials and distinguished party leaders–are able to vote.

The Democratic National Convention begins on August 19th.