Joe Biden announces he is running for president again, setting up possible Trump rematch

The announcement comes exactly four years after his last campaign kickoff.

Biden announced his 2024 campaign in a pre-recorded video.

"The question we are facing is whether in the years ahead we have more freedom or less freedom. More rights or fewer," he said in the video, entitled 'Freedom,' which was posted to his social media account early Tuesday morning.

"This is not a time to be complacent. That’s why I’m running for reelection," he said.

The video announcement focuses on Biden's closing argument to the country, making his case for four more years in office to "finish this job" -- a line he previewed during his State of the Union address in February.

"Every generation of Americans has faced a moment when they’ve had to defend democracy. Stand up for our personal freedoms. Stand up for the right to vote and our civil rights. And this is our moment," Biden says in the video. "Let’s finish this job, I know we can."

As part of that closing argument, the president also calls out "MAGA extremists" for attacking "bedrock freedoms" in the video.

Vice President Kamala Harris, again joining Biden on the ticket, is also featured prominently throughout the video.

Biden later Tuesday appeared before a friendly union audience in Washington, D.C., for his first post-announcement remarks, in which he touted his "Investing in America" agenda and continued to hit out at MAGA Republicans, but not addressing his announcement directly.

"I'm here because there's no better place to talk about the progress we've made together and wouldn't be made without you," he told the crowd. "And that's not hyperbole, that’s a fact. Our economic plan is working. We now have to finish the job."

The audience erupted into chants of "let's go Joe" and "four more years" as Biden spoke.

Biden's 2024 campaign will be managed by Julie Chávez Rodríguez, a senior adviser to the president at the White House, and the granddaughter of labor leader Cesar Chávez.

Quentin Fulks, who previously served as campaign manager Sen. Rev. Raphael Warnock’s 2022 reelection campaign, will serve as principal deputy campaign manager.

The campaign is also announcing a slate of national co-chairs, including Rep. Lisa Blunt-Rochester, Rep. Jim Clyburn, Sen. Chris Coons, Sen. Tammy Duckworth, Rep. Veronica Escobar, Jeffrey Katzenberg and Gov. Gretchen Whitmer

Tuesday also marks four years to the day since he announced his 2020 presidential campaign.

In 2019, he pitched himself as a foil to then-President Trump -- who he warned could "forever and fundamentally alter the character of this nation" as Trump went on to assail him as infirm.

Now, Biden is poised to potentially face Trump again, if Trump wins the Republican presidential nomination. The former president has already launched his own campaign and remains a dominant figure in his party: He led possible Republican challengers by double digits in an NBC News poll conducted earlier this month.

Biden notched several major legislative wins during his first two years in office, with a Democratic majority in Congress, and won significant and occasionally bipartisan investments in infrastructure, climate change, health care and COVID-19 relief, among other areas.

But questions about his age are sure to continue to swirl around his reelection campaign. At 80, Biden is already the oldest-serving president in U.S. history. At the end of a second term, he would be 86 years old.

Polls have shown most Americans -- and most Democrats -- would prefer he not run again.

Nearly six in 10 Democratic-aligned adults said they didn't want to see Biden renominated, an ABC News/Washington Post poll found in February. And seven in 10 Americans, and 51% of Democrats, said in the NBC News poll this month that they did not want him to seek a second term, with half of them citing age as a "major" factor.

The White House has responded to those concerns by pointing to the schedule Biden maintains, and his doctor has said he's fit to serve as commander in chief.

"It's legitimate for people to raise issues about my age," he told ABC News anchor David Muir in February. "It's totally legitimate to do that. And the only thing I can say is, 'Watch me.'"

Voter apathy may not prove totally insurmountable: Some of the same Democratic-leaning adults polled by ABC News earlier this year later said that while they were wary of Biden running again, that wouldn't push them toward Republicans like Trump.

Similarly, in another poll conducted this month, while nearly half of Democrats said they didn't want Biden to run again, 78% of them said they approved of the job he's doing.

Biden's age may be put to the test by the more rigorous demands of a campaign that does not take place in the throes of a pandemic, as the last one did.

In 2020, the spread of COVID-19 led Biden to severely restrict his travel and make much of his electioneering virtual. This time, the president will likely hit the road much more than he had before.

Biden has in recent months been increasingly clear that he intended to run -- while also putting off an official announcement, even as two long shot primary challengers, Marianne Williamson and Robert F. Kennedy Jr., said they were also seeking the Democratic nomination.

But the party's history-bucking success in last year's midterm elections helped to quell chatter in Washington over whether the president should seek another term. And since his State of the Union speech in February, he has repeatedly told crowds he wants to "finish the job" -- on health care, abortion rights, gun regulations and a host of other issues.

Since then, he has toured the country touting his accomplishments, including his legislative wins.

In the lead-up to Tuesday's announcement, he's also argued there has been a domestic manufacturing renaissance during his presidency, with hundreds of thousands of jobs created and hundreds of millions of dollars in private investment.

Beyond massive spending bills for infrastructure and pandemic relief, Biden has also helped broker the passage of laws that promote the domestic manufacture of semiconductor chips and clean energy technology; raise taxes on corporations; and carry out the most significant gun reform measures in decades.

But those gains all came with Democrats in full control of Congress. Since January, Republicans have held the majority in the House, bent on blocking Biden's priorities while, they say, serving as a check on the administration, including investigating his conduct.

In pushing for Biden to agree to cut federal government spending, conservatives have also created a potentially catastrophic challenge by refusing to raise the country's debt ceiling. That threatens an unprecedented national default unless the president agrees to negotiate, which he refuses to do as long as the talks are tied to the debt limit.

How that dispute plays out could shape the narrative heading into 2024.