Joe Biden is out of the presidential race. What happens now?

President Joe Biden ended his campaign Sunday, saying that it is in the "best interest" of the Democratic Party and the nation that he "stand down" and end his reelection bid.

The president threw his support behind Vice President Kamala Harris and said he will address the nation later this week.

"It has been the greatest honor of my life to serve as your president," Biden wrote in a letter posted to social media.

Biden’s decision to exit the race marks a stunning end for the 81-year-old president’s political career. Biden will not resign his role as president and will remain in the White House until January.

The president faced significant pressure from his own party to end his campaign after a disastrous debate against former President Donald Trump in June. Democrats worried that Biden was not up to the task of campaigning against Trump or running the country for another four years.

For weeks, Biden insisted he would remain in the race and was the best chance Democrats had to defeat Trump. But as the calls grew louder – and the Democratic National Convention grew closer – Biden reconsidered. Trump was already leading in battleground state polls before the debate, and his margins have only grown.

“I believe it is in the best interest of my party and the country for me to stand down and to focus solely on fulfilling my duties as president for the remainder of my term,” Biden said.

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What does Joe Biden ending his campaign mean for Arizona?

There's ample time in Arizona to get a new Democrat on the ballot ahead of the November election. Ballots aren't finalized until late summer and the first ballots don't go out until Sept. 21.

It's unclear whether another Democrat will have a better shot at winning Arizona than Biden, experts say. Biden won Arizona by fewer than 11,000 votes in 2020, the smallest margin of any state on the electoral map. Biden faced calls from Arizona's congressional Democrats to exit the race after the debate or at least prove to voters that he could run.

Biden was behind Trump in Arizona before he dropped out, according to statewide polls. Trump led the race with 51% of support to Biden's 46% in June, according to a Fox News poll conducted in June. Those numbers sank even lower in July.

An Emerson College poll conducted after the debate and Trump's attempted assassination showed Biden with 36% of support in Arizona when third-party candidates are added to the mix. Biden was 10 percentage points behind Trump in Arizona in that poll. The nonpartisan Cook Political Report, which handicaps political races, has shifted its Arizona Electoral College rating from a toss-up to “lean Republican.”

Biden faced particular issues among voters, who have said for months that he was too old to seek another term. Any Democrat is likely to face a challenge, though, because polls show more than three-quarters of voters here say the economy is in trouble and two-thirds think the country is headed in the wrong direction under the Democratic administration.

Did Biden endorse Vice President Kamala Harris? 

Biden endorsed Harris to replace him on the ticket shortly after announcing he would exit the race. He thanked Harris for serving as his second-in-command in the White House and told Democrats it is "time to come together and beat Trump.

"My very first decision as the party nominee in 2020 was to pick Kamala Harris as my Vice President. And it's been the best decision I've made. Today I want to offer my full support and endorsement for Kamala to be the nominee of our party this year," Biden said. "Democrats — it's time to come together and beat Trump. Let's do this."

For weeks, Harris has been floated as a potential replacement for Biden and has been campaigning in the battleground states that Democrats need to win to keep ahold of the White House. Harris has been to Arizona six times during her time in the Biden administration, campaigning on abortion rights and promoting the president's economic agenda.

Second gentleman Doug Emhoff was in the state as recently as Friday to campaign for the Biden-Harris ticket and catch the beginning of the WNBA All-Star weekend in Phoenix. He said during that trip that voters should not focus on the "drama" about whether Biden would drop out of the race.

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Who will replace Biden on the presidential ballot?

There are 29 days until Democrats gather in Chicago for the Democratic National Convention. It's not clear who the party's nominee will be. Democrats had planned to nominate Biden before the convention formally began to meet an earlier ballot deadline in Ohio.

Some Democrats say the party should nominate Harris, who was running alongside Biden and will have the most seamless access to his campaign operation and war chest. Others, though, have floated could-be candidates like Michigan Gov. Gretchen Whitmer, Pennsylvania Gov. Josh Shapiro, Illinois Gov. J.B. Pritzker and California Gov. Gavin Newsom. Arizona Sen. Mark Kelly's name is also on the list, along with a number of other Democrats. The party will also need to select a vice-presidential running mate for its eventual presidential nominee.

Some Arizona delegates to the DNC said on Sunday that they would support her at the convention. Paul Weich, a DNC delegate for Arizona and an attorney, said he plans to vote for Harris. He said Harris delivered "powerful" remarks on abortion when she came to the state last month.

“As we move forward as a party and as a country, we must come together and rally behind Vice President Kamala Harris as our next president of the United States,” Markus Ceniceros, another Arizona DNC delegate, told The Republic in a text message. “I look forward to voting for Vice President Kamala Harris at the DNC convention in Chicago and defeating Donald Trump.”

For its part, the party did not name any possible replacements for Biden but said Americans will hear from the Democratic National Committee “in short order” about choosing a new candidate.

“The work that we must do now, while unprecedented, is clear. 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. 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,” DNC Chair Jaime Harrison said in a written statement.

What are Republicans saying?

Trump slammed Biden in a statement on Truth Social, saying that “Crooked Joe Biden is the Worst President, by far, in the History of our Nation" and shifting his focus to his next opponent.

“He was not fit to serve from the very beginning, but the people around him lied to America about his Complete and Total Mental, Physical, and Cognitive Demise. Whoever the Left puts up now will just be more of the same,” Trump said.

Others in the GOP echoed that sentiment. Rep. Paul Gosar, R-Ariz., said that party leaders “gave the middle finger” to voters who cast ballots for Biden during the primary process.

“By rigging their own election and forcing Joe Biden to quit, billionaire Democrat donors, Hollywood leftists and Democrat party elitists just gave the middle finger to the 14 million Democrats who selected Biden to be their nominee. The Democrat coup is complete,” Gosar said in a written statement.

Rep. Andy Biggs, R-Ariz., took it a step further, calling on Biden to resign the presidency along with his campaign.

“Joe Biden is too weak and feeble to be prosecuted. He is too weak and feeble to campaign. How is he strong enough to continue serving as Commander in Chief of the strongest nation in the world? Joe Biden ought to step down,” Biggs said on social media.

This article originally appeared on Arizona Republic: Biden supports Harris, calls to beat Trump after dropping from race