Biden dropped out of the race. How will Democrats pick a nominee?

President Joe Biden’s decision to drop out of the 2024 presidential race begins a process that has not occurred in American politics in more than five decades: The presidential nominee will now be chosen by delegates to the Democratic National Convention without the result predetermined by a year of primary votes.

In a statement Sunday, DNC Chair Jaime Harrison said the party would provide details soon on next steps. But here’s what we know so far about how this process will go:

The convention is scheduled to take place Aug. 19 through Aug. 22 in Chicago.

Delegates are considered “pledged” to certain candidates. While they’re presumed to support the candidate they’re pledged to, they aren’t technically required to do so. There are 3,934 of these delegates, most of whom were pledged to Biden before this week.

On the other hand, superdelegates are considered “unpledged” or “automatic,” who are technically not committed to any candidate, regardless of the primary results.

Superdelegates include federal elected officials, governors, party leaders or former leaders, and DNC committee members.

Pledged delegates vote on the nominee at the convention, and if the majority doesn’t decide on a nominee, superdelegates join in to vote in a second round, and any further rounds.

There will be 3,949 delegates this year, which means a nominee will require 1,975 votes to win the first round.

There will be nearly 4,700 delegates this year when superdelegates are included.

Delegates are elected in primaries or caucuses at the state level. They are typically party activists, political leaders, or early supporters of a candidate.

Pennsylvania will send 159 delegates to the DNC. All of them were committed to Biden before his withdrawal.

According to DNC rules, delegates are pledged to vote for the nominee their district chose in the primary election in “good conscience.” But Biden’s exit from the race changes those dynamics, leaving delegates bound only to attempt to reflect the desires of the voters who chose them.

The vast majority of the 4,700 delegates are pledged to Biden. But just over two dozen are “uncommitted” following a protest movement against his administration’s policies in Israel.

Biden endorsed Vice President Kamala Harris to be the new nominee. But DNC rules do not allow him to pass his delegates onto her. And that endorsement does not guarantee another candidate won’t enter the race.

Following Biden’s announcement, Harrison, the DNC chair, focused on the process, but stopped short of declaring support for Harris.

“In the coming days, the Party will undertake a transparent and orderly process to move forward as a united Democratic Party with a candidate who can defeat Donald Trump in November,” Harrison said. “This process will be governed by established rules and procedures of the Party. Our delegates are prepared to take seriously their responsibility in swiftly delivering a candidate to the American people.”

David Becker, executive director of the Center for Election Innovation and Research, noted that the delegates bound to Biden were specifically picked because of their loyalty to the president.

“These people are going to pay a lot of attention to what the president wants them to do,” he said.

According to DNC rules, any nominations for presidential candidates must be submitted by 6 p.m. the day before nomination votes are scheduled to take place.

Those nominations must be accompanied by a petition signed by at least 300 delegates, but no more than 600.

During the nomination day itself, each candidate would be allotted 20 minutes for the individuals nominating them to speak on their behalf before a public roll call vote.

Democrats had initially planned to hold a virtual nomination this month, but the party delayed that vote until at least August after pressure from congressional Democrats. The party could move forward with that process without Biden or it could wait until its convention begins in Chicago.

It’s possible Harris will be the only nominee. If there are others, a more extensive voting process will occur.

In order to be awarded the nomination, a candidate must have a majority of delegates. If no candidate has a majority of delegates, then a second vote will take place. Superdelegates can begin voting if it goes to a second ballot. That process will continue until one candidate has amassed a majority of votes.

The same process would repeat for a vice presidential candidate.

“Getting delegates to vote for you is not as simple as being the only person left in the room. You have to actually get to those delegates or get surrogates to those delegates and talk to them,” TJ Deluca, a DNC delegate from Delaware County, said in an interview last week.

Deluca said last week he expected there would be a lot of confusion at the convention, but also a lot of people ready and willing to step forward to help.

House Speaker Mike Johnson, a Louisiana Republican and ally of former President Donald Trump, has warned that Democrats’ efforts to replace Biden as the nominee could set off lawsuits, which some conservatives have threatened.

Kevin Greenberg, an election lawyer who is a DNC delegate for the 3rd Congressional District in Philadelphia, said he’s “not at all” concerned about legal challenges because conventions are meant to establish the nominee for the ballot in all 50 states. Historically, primaries haven’t always played a part in the process.

“This is how it works, this is how it’s supposed to work, and it will work how it’s supposed to,” said Greenberg, who plans to vote for Harris as the presidential nominee.

The vice presidential nomination takes place in a separate vote at the convention than the president. Typically, the already-chosen vice president is ratified at the convention.

Harris could choose a potential running mate, but delegates are not bound to accept that choice at the convention.

Until the 1970s, presidential candidates were nominated in conventions. That changed after the brokered 1968 Democratic National Convention in Chicago and the ensuing riot.

The Democratic Party changed its rules after that convention, requiring delegates to represent the presidential preferences of those voters who chose them.

This year’s convention will be the first test of the Democratic Party’s rules for picking a candidate during a convention since that change in 1972.

Deluca, the delegate, said the new rules were designed to be transparent and force candidates to campaign for the votes of DNC delegates.

“There are no smoke-filled back rooms anymore, and it’s not just because they banned smoking inside,” he said.

Campaign finance experts generally agree that if Harris is the nominee, she could take on Biden’s campaign chest since it was also set up in her name. His campaign recently reported $91 million cash on hand, and combined with allied Democratic campaign committees, he had access to more than $240 million.

Following his announcement Sunday, Biden’s campaign wasted no time passing his war chest to his vice president.

His campaign committee changed its name to Harris for President shortly before 5 p.m. on Sunday, and moments later, Biden sent out a campaign email urging his supporters to donate to Harris’ campaign for president.

Party accounts can still support the nominee if Democrats nominate someone other than Harris, but the Biden-Harris account would have more restrictions. Legal experts say the Biden-Harris account could become an independent expenditure political action committee, but could not just transfer its balance directly to a new nominee. Functioning as an independent expenditure committee has downsides, like not being able to coordinate with the campaign about messaging, according to Greenberg.

Becker, with the Center for Election Administration and Research, said the campaign could also transfer the funds directly to the Democratic National Committee or to an existing PAC.

Pennsylvania’s delegates voted unanimously Monday to endorse Harris as the party’s nominee for president.

The Associated Press contributed to this article.