But on Tuesday, as unlikely as it may have seemed before, Americans will choose either Trump or Harris to serve as the next president. It is the final chapter in one of the most bewildering, unpredictable and important sagas in political history. For once, the word “unprecedented” was not overused.

“If somebody told you ahead of time what was going to happen in this election and you tried to sell it like a book, nobody would believe it,” said Neil Newhouse, a Republican pollster with more than four decades of experience. “It energized the country and polarized it. And all we can hope for is that we come out of it better in the end.”

History has been and will be made. The United States has never elected a president who was convicted of a crime. Trump survived not one, but two assassination attempts. Biden dropped out in the middle of an election year, and Harris could become the first female president. The fundamental principles about democracy in the most powerful nation on earth will be tested like never before after the Civil War.

And that’s not to mention the background of simultaneous conflicts in Europe and the Middle East, hacking by foreign governments, an increasingly normalized blizzard of disinformation, and the intimate involvement of the world’s richest man, Elon Musk.

For now, the only thing the country can agree on is that no one knows how the story will end.

Republicans could be done with Trump after January 6, 2021.

It was the day he unleashed his supporters with bogus claims of voter fraud, directed them to march on the US Capitol as Congress ceremoniously certified Biden’s electoral victory, then stood by as riots threatened lawmakers and his own vice president.

But not enough Republicans joined with Democrats to impeach Trump in an impeachment trial, clearing the way for him to run for office again.

Trump began plotting a comeback even as some leaders in his party hoped he would be eclipsed by Ron DeSantis, the governor of Florida, or Nikki Haley, the former governor of South Carolina who served as Trump’s ambassador to the United Nations.

In the year after Trump announced he would run against Biden, he has faced criminal charges four times. Two of the indictments were related to his attempts to overturn his election defeat. Another involved his refusal to return classified documents to the federal government after he left office. Trump has pleaded not guilty to all charges, and none of those cases have been resolved.

However, a fourth indictment in New York made Trump the first president in US history to be criminally convicted. A jury found him guilty on May 30 of falsifying business records over hush money payments to a porn star who claimed he had an affair.

None of this has slowed Trump, who has virtually ignored his opponents during the primaries as he moves toward the Republican presidential nomination. A photo from one of his arrests was adopted by his followers as a symbol of resistance to a corrupt system.

Trump’s candidacy has capitalized on anger over inflation and frustration over migrants crossing the southern border. He also considered Biden too old for the job, even though he is only four years younger than the president.

But Democrats also believed Biden, 81, would be better off considering retirement rather than a second term. So when Biden struggled through a presidential debate on June 27 — losing his train of thought, appearing confused, stumbling through answers — he faced mounting pressure within his own party to drop out of the race.

While Biden was facing a political crisis, Trump went to an outdoor rally in Butler, Pennsylvania on July 13. A young man backed up the police, climbed to the top of a nearby building and fired several shots with a semi-automatic rifle.

Trump grabbed his ear and fell on the stage. As Secret Service agents swarmed around him, he stood up with a streak of blood on his face, thrust his fist into the air and shouted “fight, fight, fight!” An American flag stretched overhead.

It was an instantly iconic moment. Trump’s path to the White House seemed clearer than ever—perhaps even inevitable.

The vice president was preparing to do a puzzle with her granddaughters on the morning of July 21 when Biden called. He had decided to end his re-election bid and endorse Harris as his replacement.

He spent the rest of the day making dozens of phone calls to line up his support and had enough to secure the nomination in two days.

It was a stunning reversal of fortune. Harris fizzled out when he ran for president four years earlier, dropping out before the first Democratic contest. Biden resurrected his political career by choosing her as his running mate and became the first woman, person of color, and person of South Asian descent to serve as vice president.

But Harris’ struggles didn’t end there. She fumbled questions about immigration, oversaw large-scale turnover in her office, and faded into the background rather than use her historic status as a platform.

All of that began to change on June 24, 2022, when the US Supreme Court struck down the nationwide right to abortion enshrined in Roe v. Wade. Harris became the White House’s chief advocate on an issue that reshaped American politics.

It also proved to be more agile than before. Shortly after returning from a week-long trip to Africa, her team orchestrated an emergency trip to Nashville so Harris could show support for two Tennessee lawmakers who were expelled for protesting for gun control.

Meanwhile, Harris was networking with local politicians, business leaders and cultural figures to get ideas and build connections. When Biden dropped out, she was better positioned than many realized to seize the moment.

The day after she became a candidate, Harris went to Wilmington, Delaware, to visit campaign headquarters. Staff members had spent the morning printing out “Kamala” and “Harris for President” signs to stick next to outdated “Biden-Harris” posters.

There are 106 days left until the end of the elections.

While speaking to campaign staff in Wilmington, Harris used a line that has become a mantra, chanted by supporters at rallies across the country. “We’re not going back,” she declared.

It’s a fitting counterpoint to Trump’s “make America great again” slogan he’s used since launching his first campaign more than eight years ago.

The two candidates have almost nothing in common, which was on display on September 10 when Harris and Trump met for the first time for their only televised debate.

Harris has promised to restore abortion rights and use tax breaks to support small businesses and families. She said she would be “a president for all Americans.”

Trump took credit for nominating judges who helped overturn Roe, pledged to protect the US economy with tariffs and made false claims about migrants eating people’s pets. He called Harris “the worst vice president in the history of our country.”

Harris was widely seen as gaining the upper hand. Trump insisted he had won, but refused a second debate. The race remained remarkably close.

Pundits and pollsters have spent the past few weeks trying to pinpoint any changes in the candidates’ chances. Microscopic changes in public opinion could change the outcome of an election. It could take days to count enough votes to determine who wins.

The result, whenever it becomes clear, could be just another surprise in a campaign that has been full of them.