Joe Biden’s announcement today that he is running for president in 2024 is at once entirely predictable and exceptionally improbable.

In a video released early this morning, the president formally announced his reelection bid, seeking to swipe a traditional Republican theme—freedom—for his own campaign.

“That’s been the work of my first term: to fight for our democracy, to protect our rights,” Biden says. “To make sure that everyone in this country is treated equally, that everyone is given a fair shot.”

But he accuses “MAGA extremists” of seeking to cut Social Security (true of many Republicans, though not of Donald Trump), prohibit abortion, make voting harder, and ban books.

“The question we’re facing is whether in the years ahead we have more freedom or less freedom. More rights or fewer,” Biden says. “I know what I want the answer to be, and I think you do too. This is not a time to be complacent.”

The video is classic Bidenalia: aviators and hugs, snapshots of union workers and of Supreme Court Justice Ketanji Brown Jackson. “This is our moment,” he says. “Let’s finish this job.”

If this is Biden’s moment, it’s not one that many people saw coming just a few years ago. The announcement is predictable because Biden has been signaling that he would run for a second term for years now—a signal that many people took to be a feint at first, but that most had gradually come to believe was real. And it’s predictable because an incumbent president with a robust list of accomplishments and no serious primary challengers (sorry, Robert F. Kennedy Jr.) is all but certain to try for four more years.

Yet for a long time, the very idea that Biden would ever be president seemed dubious, despite his long-standing desire to hold the office. He failed in 1988 and 2008, and reluctantly passed on running in 2016. Right up until the February 29, 2020, South Carolina Democratic primary (how’s that date for improbable?), what everyone thought was Biden’s final attempt also seemed destined for failure. Then he turned things around, cruising through the Democratic field. That spring and summer was a tumultuous time in the United States, when much of normal life shut down because of COVID and widespread unrest over police violence occurred. By November, Biden was the favorite to beat Trump—which he did, though not by as much as some polls predicted—and then he finally attained his lifelong goal.

Even after Biden took office, doubts persisted that he’d try for a second term. He is already the oldest president in American history, and at times his age has shown. His presidency has seen some hiccups—most notably, inflation and the disastrous end to the American occupation of Afghanistan. But Biden has also assembled a record of achievement that rivals or exceeds the first term of any Democratic president for decades, and far surpasses what most people expected. (Biden has long profited from beating low expectations.)

Another reason for doubts about a Biden reprise was that he is not especially popular. Although his numbers have rebounded somewhat, he remains underwater. Yet Biden has managed to maintain the coalition that put him in office, in part because revulsion over the January 6 insurrection and the ongoing threat of another Trump presidency have kept it together. He’s also fended off any primary challenge from the party mainstream. In doing this, he benefits from structural advantages of the presidency; from co-opting likely challengers, such as Vice President Kamala Harris and Transportation Secretary Pete Buttigieg; and from what I’ve called the catch-24: He has made clear he’ll run unless he thinks another moderate can beat Trump if he’s the GOP nominee, but no moderate will run as long as Biden is running.

During the 2020 primary, Biden tried to neutralize concerns about his age as well as his station as a vestige of the Democratic Party’s past by presenting himself as a transitional figure. “Look, I view myself as a bridge, not as anything else,” he said. “There’s an entire generation of leaders you saw stand behind me. They are the future of this country.”

With today’s announcement, we now see that the bridge is longer than it might have seemed at the time. One question is what Biden’s persistence means for members of the generation he mentioned. Does he stifle them and the chance at a new Democratic Party by running again? Or does he allow more time for a stronger bench to develop? Harris and Buttigieg have arguably seen their stars tarnished—or at least not burnished—by their service in the Biden administration.

Extra time could give either of them the chance to improve their public profile, or to self-sabotage. It could also allow other Democrats, perhaps Governors Gretchen Whitmer of Michigan or Gavin Newsom of California, to prepare for the national stage. If Biden is able to win reelection, expect questions about whether he will be able to serve another four years—or move aside in favor of his vice president before the 2028 election. But before then, a long and likely rough campaign is ahead.

This cheat sheet tracks who’s in, out, up, and down in the 2024 races. It will be updated as the campaign develops, so check in regularly.

DEMOCRATS (Joshua Roberts / Getty) Joe Biden

Who is he?
After decades of trying, Biden is the president of the United States.

Is he running?
Yes. Biden formally announced his run on April 25.

Why does he want to run?
Biden’s slogan is apparently “Let’s finish the job.” He centered his launch video on the theme of freedom, but underlying all of this is his apparent belief that he may be the only person who can defeat Donald Trump in a head-to-head matchup.

[Mark Leibovich: The case for a primary challenge to Joe Biden]

Who wants him to run?
There’s the catch. Some prominent Democrats support his bid for a second term, but voters have consistently told pollsters they don’t want him to run again.

Can he win the nomination?
Barring unforeseen catastrophe, yes. No incumbent president has lost the nomination in the modern era, and Biden has pushed through changes to the Democratic-primary process that make him an even more prohibitive favorite.

What else do we know?
Biden is already the oldest person elected president and to serve as president, so a second term would set more records.

(Chip Somodevilla / Getty) Kamala Harris

Who is she?
Harris is the vice president of the United States.

Is she running?
No, but if Biden were to bow out, she’d be the immediate favorite.

Why does she want to run?
One problem with her 2020 presidential campaign was the lack of a clear answer to this question. Perhaps running on the Biden-Harris legacy would help fill in the blank.

Who wants her to run?
Some Democrats are excited about the prospect of nominating a woman of color, but generally Harris’s struggles as a candidate and in defining a role for herself (in the admittedly impossible position of VP) have resulted in nervousness about her as a standard-bearer.

Can she win the nomination?
Not right now.

(Matthew Cavanaugh / Getty) Pete Buttigieg

Who is he?
Mayor Pete is Secretary Pete now, overseeing the Department of Transportation.

Is he running?
No, but he would also be a likely candidate if Biden stepped away.

Why does he want to run?
Just as he was four years ago, Buttigieg is a young, ambitious politician with a moderate, technocratic vision of government.

Who wants him to run?
Buttigieg’s fans are passionate, and Biden showed that moderates remain a force in the party.

Can he win the nomination?
Not at this moment.

(Scott Olson / Getty) Bernie Sanders

Who is he?
The senator from Vermont is changeless, ageless, ever the same.

Is he running?
No, but if Biden dropped out, it’s hard to believe he wouldn’t seriously consider another go. A top adviser even says so.

Why does he want to run?
Sanders still wants to tax billionaires, level the economic playing field, and push a left-wing platform.

Who wants him to run?
Sanders continues to have the strong support of a large portion of the Democratic electorate, especially younger voters.

Can he win the nomination?
Two consecutive tries have shown that he’s formidable, but can’t close. Maybe the third time’s the charm?

(Chip Somodevilla / Getty) Gretchen Whitmer

Who is she?
Whitmer cruised to a second term as governor of Michigan in 2022.

Is she running?
No.

Why does she want to run?
It’s a little early to know, but her reelection campaign focused on abortion rights.

Who wants her to run?
Whitmer would check a lot of boxes for Democrats. She’s a fresh face, she’s a woman, and she’s proved she can win in the upper Midwest against a MAGA candidate.

Can she win the nomination?
Not if she isn’t running.

(Lucas Jackson / Reuters) Marianne Williamson

Who is she?
If you don’t know Williamson from her popular writing on spirituality, then you surely remember her somewhat woo-woo Democratic bid in 2020.

Is she running?
Yes. Williamson announced her campaign on March 4 in D.C.

Why does she want to run?
“It is our job to create a vision of justice and love that is so powerful that it will override the forces of hatred and injustice and fear,” she said at her campaign launch. She has also said that she wants to give voters a choice. “The question I ask myself is not ‘What is my path to victory?’ My question is ‘What is my path to radical truth-telling?’ There are some things that need to be said in this country.”

Who wants her to run?
Williamson has her fans, but she doesn’t have a clear political constituency.

Can she win the nomination?
Nah.

(Brian Cassella / Chicago Tribune / Getty) J. B. Pritzker

Who is he?
The governor of Illinois is both a scion of a wealthy family and a “nomadic warrior.”

Is he running?
No.

Why does he want to run?
After years of unfulfilled interest in elected office, Pritzker has established himself as a muscular proponent of progressivism in a Democratic stronghold.

Who wants him to run?
Improbably for a billionaire, Pritzker has become a darling of the Sanders-style left, as well as a memelord.

Can he win the nomination?
Not now.

(Brian Cassella / Chicago Tribune / Getty) Robert F. Kennedy Jr.

Who is he?
The son of a presidential candidate, the nephew of another, and the nephew of a president, Kennedy is a longtime environmental activist and also a chronic crank.

Is he running?
Yes. He announced his run on April 19.

Why does he want to run?
Running for president is a family tradition—hell, he wouldn’t even be the first Kennedy to primary a sitting Democrat. You can expect a campaign arranged around his esoteric combination of left-wing interests (the environment, drug prices) and right-wing causes (vaccine skepticism, anger about social-media “deplatforming”).

Who wants him to run?
Who knows? One report says Steve Bannon encouraged his run in order to stoke chaos, which checks out. Kennedy’s wife, the actor Cheryl Hines—with whom he has clashed over vaccines—is at least willing to tolerate it. “I’ve passed the biggest hurdle, which is my wife has green-lighted it,” Kennedy said.

Can he win the nomination?
No.

REPUBLICANS (Joe Raedle / Getty) Donald Trump

Who is he?
You know him and you love him. Or hate him. Probably not much in between.

Is he running?
Yes. Trump announced his bid to return to the White House at Mar-a-Lago in November 2022.

Why does he want to run?
Revenge, boredom, rivalry, fear of prosecution, long-standing psychological hang-ups.

[Elaine Godfrey: Trump begins the ‘retribution’ tour]

Who wants him to run?
A big tranche of the GOP is still all in on Trump, but it’s a little hard to tell how big. Polling shows that his support among Republicans is all over the place, but he’s clearly not a prohibitive front-runner.

Can he win the nomination?
Yes, but past results are no guarantee of future success.

What else do we know?
More than we could possibly want to.

(Joe Raedle / Getty) Ron DeSantis

Who is he?
The second-term governor of Florida, DeSantis was previously a U.S. representative.

Is he running?
Not officially, but clearly the answer is yes. DeSantis is getting a campaign and super PAC up and running, marshaling donors, and inserting himself into national politics. He reportedly might not announce until May or June.

Why does he want to run?
DeSantis offers the prospect of a synthesis of Trump-style culture war and bullying and the conservative politics of the early-2010s Republican Party.

Who wants him to run?
Members of the Republican establishment who want a pugilistic alternative to Trump, disaffected MAGA types, and maybe Jeb!

[From the March 2023 issue: How did America’s weirdest, most freedom-obsessed state fall for an authoritarian governor?]

Can he win the nomination?
No one quite knows how a Trump-DeSantis battle will play out, but it seems very possible.

(Roy Rochlin / Getty) Nikki Haley

Who is she?
Haley, the daughter of immigrants, was governor of South Carolina and then ambassador to the United Nations under Trump.

Is she running?
Yes. She announced her campaign on February 14, saying, “Time for a new generation.”

Why does she want to run?
Perhaps as a MAGA-friendly alternative to Trump? It’s hard to say, as my colleague Tim Alberta has chronicled. Haley served under Trump, condemned him over January 6, said she wouldn’t run if he ran, and now is running anyway.

[Sarah Isgur: What Nikki Haley can learn from Carly Fiorina]

Who wants her to run?
That’s also hard to say, but if DeSantis stumbles in the spotlight, she could make a play for his supporters.

Can she win the nomination?
Dubious.

(Dylan Hollingsworth / Bloomberg / Getty) Vivek Ramaswamy

Who is he?
A 37-year-old biotech millionaire with a sparkling résumé (Harvard, then Yale Law, where he became friends with Senator J. D. Vance), Ramaswamy has recently become prominent as a crusader against “wokeism” and environmental, social, and governance (ESG) investing.

Is he running?
Yes. He announced his campaign on February 21.

Why does he want to run?
“We’re in the middle of a national identity crisis,” Ramaswamy said in a somewhat-hectoring launch video. “Faith, patriotism, and hard work have disappeared, only to be replaced by new secular religions like Covidism, climatism, and gender ideology.”

Who wants him to run?
As The New Yorker found in a long profile in December, he has some avid fans. So far, little evidence suggests this amounts to a winning coalition.

Can he win the nomination?
Almost certainly not. At this stage, Ramaswamy gives off Steve Forbes/Herman Cain/Morry Taylor vibes—an interesting character from the business world, but not a contender. Then again, Trump once did too.

(Alex Wong / Getty) Asa Hutchinson

Who is he?
Hutchinson, the formerly longtime member of Congress, just finished a stint as governor of Arkansas.

Is he running?
Yes. Hutchinson announced on April 2 that he is running. It would have been funnier to announce a day earlier, though.

Why does he want to run?
At one time, Hutchinson was a right-wing Republican—he was one of the managers of Bill Clinton’s impeachment—but as the party has changed, he finds himself closer to the center. He’s been very critical of Trump, saying that Trump disqualified himself with his attempts to steal the 2020 election. Hutchinson is also unique in the field for having called on Trump to drop out over his indictment in New York.

Who wants him to run?
Some old-school Republicans would welcome his candidacy, but it’s hard to imagine a groundswell.

Can he win the nomination?
Unlikely.

(Drew Angerer / Getty) Larry Hogan

Who is he?
Hogan left office this year after serving two terms as governor of Maryland.

Is he running?
No. After giving a campaign “very serious consideration,” Hogan ruled himself out on March 5, saying he was worried that too large a field would help Trump win the nomination once more.

Why did he want to run?
Hogan argued that his experience of governing a very blue state as a Republican is a model: “We’ve been really successful outside of Washington, where everything appears to be broken and nothing but divisiveness and dysfunction.” He’s also a vocal critic of Donald Trump.

Who wanted him to run?
Moderate, business-friendly “Never Trump” Republicans love Hogan.

Could he have won?
No.

(John Locher / AP) Chris Sununu

Who is he?
The governor of New Hampshire, he’s the little brother of former Senator John E. Sununu and son of former White House Chief of Staff John H. Sununu.

Is he running?
“Maybe I run, maybe I don’t,” he said in early February. But he passed on a Senate run last year and just created a fundraising vehicle that typically presages a candidacy.

Why does he want to run?
Sununu seems disgusted by a lot of Washington politics and sees his success in New Hampshire, a purple-blue state, as a model for small-government conservatism.

Who wants him to run?
Trump-skeptical Republicans, old-school conservatives.

Can he win the nomination?
Maybe.

(David Becker / The Washington Post / Getty) Tim Scott

Who is he?
A South Carolinian, Scott is the only Black Republican senator.

Is he running?
Probably. On April 12, he launched an exploratory committee, just as he visited Iowa. He also says he doesn’t plan to run for another Senate term.

Why does he want to run?
Unlike some of the others on this list, Scott doesn’t telegraph his ambition quite so plainly, but he’s built a record as a solid Republican. He was aligned with Trump, but never sycophantically attached.

Who wants him to run?
Scott’s Senate colleagues adore him.

Can he win the nomination?
Who knows? The soft-spoken Scott is untested in this kind of campaign.

(Scott Olson / Getty) Mike Pompeo

Who is he?
Pompeo, a former member of Congress, led the CIA and was secretary of state under Trump.

Is he running?
No. On April 14, Pompeo announced he wasn’t running. “This is not that time or that moment for me to seek elected office again,” he said.

Why did he want to run?
Pompeo has always been ambitious, and he seems to think he can combine MAGA proximity with a hawkish foreign-policy approach.

Who wanted him to run?
That’s not entirely clear.

Could he have won the nomination?
Maybe, but probably not.

(Misha Friedman / Getty) Glenn Youngkin

Who is he?
Youngkin, the former CEO of the private-equity Carlyle Group, was elected governor of Virginia in 2021.

Is he running?
Probably not. He said on May 1 that he wasn’t running “this year.” That’s a little short of Shermanesque, but it’d be hard to mount a real campaign starting in the 2024 calendar year—unless other Republicans self-destruct, which could happen.

Why does he want to run?
Youngkin is a bit of a cipher; he ran largely on education issues, and has sought to tighten abortion laws in Virginia, so far to no avail.

Who wants him to run?
Republicans who see him as able to run on Trumpy cultural issues while keeping some distance from Trump.

Can he win the nomination?
Certainly not if he isn’t running.

(Megan Varner / Getty) Mike Pence

Who is he?
The former vice president, he also served as governor of Indiana and U.S. representative.

Is he running?
Pretty likely, though he hasn’t declared.

Why does he want to run?
Pence has long harbored White House dreams, and he has a strong conservative-Christian political agenda. His time as Trump’s VP both makes him more plausible and probably rules him out, because he’s fallen afoul of his old boss.

Who wants him to run?
Conservative Christians, rabbit lovers.

[Read: Nobody likes Mike Pence]

Can he win the nomination?
It’s hard to see it happening.

(Mandel Ngan / Getty) Francis Suarez

Who is he?
Suarez is the popular second-term mayor of Miami and the president of the U.S. Conference of Mayors.

Is he running?
He’s been telling reporters for months that he’s considering, most recently in March.

Why does he want to run?
Suarez touts his youth—he’s 45—and said in October 2022, “I’m someone who believes in a positive aspirational message. I’m someone who has a track record of success and a formula for success.” He’s also someone who voted against the Republican Ron DeSantis in the 2018 governor’s race and did not vote for Trump in 2020.

Who wants him to run?
Is there really room for another moderate-ish Republican in the race? Suarez reports that Trump said he was the “hottest politician in America after him,” but the former president is himself running, and with DeSantis a presumptive candidate, Suarez would be an underdog in his home state.

Can he win the nomination?
Highly unlikely.

(Sam Wolfe / Bloomberg / Getty) Mike Rogers

Who is he?
Rogers is a congressman from Alabam—wait, no, sorry, that’s the other Representative Mike Rogers. This one is from Michigan and retired in 2015. He was previously an FBI agent and was head of the Intelligence Committee while on Capitol Hill.

Is he running?
He is thinking about it and has formed a group with the suitably vague name “Lead America.”

Why does he want to run?
He laid out some unassailably broad ideas for a campaign in an interview with Fox News, including a focus on innovation and civic education, but it’s hard to tell what exactly the goal is here. “This is not a vanity project for me,” he added, which, okay, sure.

Who wants him to run?
“I think the Trump, Trump-lite lane is pretty crowded,” he told Fox. “The lane that is not talking about Trump, that is talking about solutions and the way forward and what the real challenges we face—I just don’t find a lot of people in that lane.” Which, again, okay?

Can he win the nomination?
Nope.

(Ida Mae Astute / Getty) Chris Christie

Who is he?
What a journey this guy has had, from U.S. attorney to respected governor of New Jersey to traffic-jam laughingstock to Trump sidekick to Trump critic. Whew.

Is he running?
He really wants to, but he is “trying to figure out” if there’s a way to run against Trump and DeSantis, he told Fox News in late March. A former aide told The New York Times that Christie “wants for sure” to run.

Why does he want to run?
Anyone who runs for president once and loses wants to run again—especially if he thinks the guy who beat him is an idiot, as Christie clearly thinks about Trump. Moreover, he seems agitated to see other Republicans trying to run without criticizing Trump.

Who wants him to run?
“I’ve had a lot of interesting conversations with donors over the course of the last few weeks,” Christie has said, as is obligatory of long-shot candidates. But he doesn’t seem to have much of a campaign-in-waiting or a clear constituency.

Can he win the nomination?
Highly doubtful.

(Todd Williamson / Getty) Larry Elder

Who is he?
A longtime conservative radio host and columnist, he ran as a Republican in the unsuccessful 2021 attempt to recall California Governor Gavin Newsom.

Is he running?
Yes. He announced his campaign on Tucker Carlson’s Fox News show on April 20.

Why does he want to run?
Glad you asked! “America is in decline, but this decline is not inevitable,” he tweeted. “We can enter a new American Golden Age, but we must choose a leader who can bring us there. That’s why I’m running for President.” We don’t have any idea what that means either.

Who wants him to run?
Impossible to say at this stage, but deep-blue California is a tough launching pad for any conservative, especially an unseasoned candidate. This recall campaign also dredged up various unflattering information about his past.

Can he win the nomination?
Hope springs eternal, but probability does not.