Now that President Joe Biden has withdrawn from the 2024 presidential race and endorsed Vice President Kamala Harris as his successor, what remains to be done before a new candidate enters the race?

Biden’s endorsement, while notable, does not mean Harris will replace him on the ticket. Much remains to be done, and the rare situation facing the Democratic Party will raise many questions heading into November.

Chicago plays a crucial role in answering these questions.

This is what happens next:

What would happen if Biden withdraws?

Biden’s decision to support Harris is not binding, as Democratic Party rules do not allow him to simply choose a successor to the nominee when delegates meet in Chicago.

According to NBC News, the Democratic Party rules outline what would happen if Biden left office before he was formally nominated.

“Keep in mind that if this unprecedented situation occurs, it’s possible the party could vote to change one of its rules around candidate replacements. And if it happens after the convention, it’s possible state laws could complicate efforts to replace Biden on specific ballots,” NBC News reported.

Reportedly, 33 states routinely follow party lines when changing nominees, but that could still pose legal challenges for Democrats as they try to put together a new ticket.

According to Politico, House Speaker Mike Johnson has indicated that legal action could be taken in at least some of these states.

If Biden withdraws before he is officially nominated in August, it could also set off a power struggle among Democrats, as there is no mechanism by which he or anyone else can appoint a chosen successor.

A majority of the roughly 4,000 pledged delegates is needed to win the party’s nomination. Biden has won 3,900, but he must release them to name a replacement nominee.

“Number one is President Biden would have to release his delegates. They’re bound by the first ballot anyway, and that’s almost all of the 4,000 delegates, Biden delegates — they’re pledged on the first ballot. The only way that works is if the Rules Committee, which controls the Biden campaign, or the president himself, releases those delegates,” Pete Giangreco, a Democratic strategist, told NBC Chicago.

Potential nominees must then collect signatures to qualify for a vote from their fellow Democrats.

“The next step in the process is then that anybody who wants to put their name forward needs signatures from 300 of those representatives, out of those 4,000, and then you start a process. The person who is most likely to get 300 signatures is VP Harris,” Giangreco.

Under recent reforms, the party’s 700-plus superdelegates (Democratic lawmakers and dignitaries) are allowed to vote only if no one wins a majority of pledged delegates in the first ballot. Their votes could thus be decisive in a contested party congress.

Since Biden’s opponents effectively failed to win any delegates during the Democratic nomination process, the congress would be virtually a clean slate. The decision would likely hinge on the delegates originally pledged to Biden.

Biden still has some influence over the delegates he has pledged, but ultimately they can vote however they want, so candidates will likely campaign aggressively to win over each individual delegate.

Once a candidate receives a majority of the delegate votes, he/she becomes the party’s nominee.

And what about the vice presidential candidate?

The same process applies to the vice-presidential position.

A majority of the delegates must agree on a candidate.

It’s unclear whether Democrats have yet to field a candidate in the event Harris leads the race, but it’s possible that many top officials are involved in the candidates.

Who could replace Biden?

Biden – as expected – endorsed Harris, writing on social media: “…Democrats — it’s time to come together and defeat Trump. Let’s do this.”

Of the potential candidates, the former California senator was seen as the most suitable candidate to replace him, but she will have some competition.

Harris would have a leg up on several of the most talked-about Democratic alternatives. She’s already on a winning presidential ticket with Biden, has spent years building goodwill with core party voters and would likely control a massive campaign fund amassed by Biden’s reelection.

A number of representatives have already indicated that they will be loyal to Harris.

“Harris is the most logical choice to continue Biden’s legacy,” said Andrew Feldman, a Democratic strategist who works closely with several state parties.

A recent poll conducted before Biden’s announcement by the AP-NORC Center for Public Affairs Research found that about 6 in 10 Democrats believe Kamala Harris would do well in the top job. About 2 in 10 Democrats don’t think she would, and another 2 in 10 say they don’t know enough to say.

Alvin Tillery, director of the Center for the Study of Diversity and Democracy at Northwestern University and a Democratic pollster, previously said Harris is the only candidate with the name recognition needed to take on Trump.

“(Of the) five other candidates running for office, only one has the name recognition to win nationally: Kamala Harris,” Tillery told NBC Chicago.

Other names that could find a spot on the ticket, either in a presidential or vice presidential role, include Kentucky Governor Andy Beshear, California Governor Gavin Newsom, Illinois Governor JB Pritzker, Michigan Governor Gretchen Whitmer, Arizona Senator Mark Kelly and Transportation Secretary Pete Buttigieg, to name a few.