MANCHESTER, N.H. — The seeds of the New Hampshire primary’s stunning conclusion can be traced back to a single day nearly 22 months ago.

In an unassuming Manchester ballroom, Donald Trump tested the message behind a possible presidential campaign. He railed against the Republican Party’s establishment and insiders to the conservative confab gathered at the Best Western Plus Executive Court Inn. And for the first time, he uttered these words to New Hampshire voters: “We have to make America great again.’’

Just minutes away on that mild April afternoon, a little-known senator from neighboring Vermont, Bernie Sanders, held a hastily organized event at the New Hampshire Institute of Politics. Sanders had driven with a single aide to the Saint Anselm College campus, where hundreds of people showed up to hear him. The room overflowed, and people had to be turned away.

On that day, Sanders and Trump delivered speeches that were starkly different in tone and policy. But they were similar in their economic populism, antiestablishment rhetoric, criticism of money in politics, and, most of all, in tapping into voters’ exasperation with the status quo.

Two years later, the results of the 2016 New Hampshire primary proved these sentiments were not fleeting or a fluke. On Tuesday, Trump and Sanders, presidential candidates, won resounding victories in New Hampshire’s primary as they captured the angry, impatient mood of an electorate ready to rebuke establishment politics.

In the Democratic race, the establishment was represented by Hillary Clinton, who suffered a 22-point loss Tuesday — the greatest defeat ever in a competitive New Hampshire Democratic primary.

Trump bested a field of eight other Republican candidates, receiving more than three times as many votes as former Florida governor Jeb Bush, the son and brother of presidents. In the same Manchester ballroom where he first tested his future presidential campaign message, Trump declared victory in the New Hampshire primary.

It was also in that same room, just a few feet from the stage, that Trump met Corey Lewandowski, his future campaign manager, in person on April 12, 2014. On that day, Trump exchanged contact information with Lewandowski, a New Hampshire resident who was then a senior staff member with Americans for Prosperity, a group funded by the conservative Koch brothers.

Lewandowski helped organize that day’s conference, The Inaugural Freedom Summit, which featured several potential presidential candidates as speakers. US Senator Ted Cruz from Texas, US Senator Rand Paul of Kentucky, former Arkansas governor Mike Huckabee, former US House speaker Newt Gingrich, and Trump spoke to anaudience of staunch conservatives and Tea Party movement faithful.

Typically at these gatherings, presidential candidates test out their speeches and messages. White House hopefuls in recent cycles had often recited their political resume, accomplishments, or spoke about traditional Republican fare like guns and God.

But this group of 2016 presidential candidates was talking about something else.

Speaking at an event funded by the Kochs, one of the richest families in the world, Cruz criticized the nation’s top 1 percent of income earners. His message: A corrupt federal government was in cahoots with the nation’s richest citizens, and that nexus of power only made the rich richer through regulations and laws that squeezed the less fortunate.

A little over a year after Mitt Romney was pounded on the airwaves for laying off workers through his private equity firm, Paul asked members of this audience to raise their hand if they had ever been laid off or fired from a job.

“If you want to grow the movement, we cannot be the party of fat cats, rich people, and Wall Street,’’ Paul said. “There is always more of the working class than the owners’ class. I am not against the owner’s class, but I want to tell the workers of America that we are on their side.’’

Then Trump, who took the stage as Frank Sinatra’s “New York, New York’’ blared on the sound system, said this: “There is something we have to do and we have to do it fast. We have to make America great again.’’

In that ballroom, the rhetoric suggested something had changed in American politics. It was a rejection of the nation’s ruling elite and the institutions they run: the government, the media, the banks, the unions, the big political donors, the education system, the insurance companies, even the church and sports figures.

But with the Koch brothers in town, Sanders had decided to hold a counter-event nearby. The raspy and often-disheveled senator had been critical of money’s increasing influence over politics, and for many Democrats, the Koch brothers were a symbol of that perceived dysfunction.

Sanders was known for his progressive economic ideals, describing himself as a democratic socialist. In 2010, he became a liberal hero when he spoke out against extending tax cuts for the highest income earners for eight-and-a-half hours on the US Senate’s floor. At the time, he was 69 years old.

Sanders had no political infrastructure in New Hampshire, and he was a full year away from announcing a presidential bid. He organized the town hall meeting just a few days ahead of time. But nearly 400 people showed up in The Institute of Politics room where similar events often attract a quarter of that crowd.

Sanders told the crowd: “What exists all over America today is that millions and millions and millions of people — working people, low-income people, young people — they look at the political process and they say ‘not for me. I don’t know what these guys are doing, but it sure is not relevant to my life.’?’’

That day nearly two years ago was the beginning of a long, strange New Hampshire campaign — featuring moments that were often stranger than fiction.

Trump repeatedly cussed on stage, and often demonstrated an uncanny ability to draw attention to himself. “Presidential selfie girls’’ traveled the state, trying to nab photos with every candidate. There was the Paul staffer who licked an opposing staffer’s video camera. Bill Clinton, the former president, awkwardly commanded an audience to laugh at his jokes. Bush told a different crowd to clap for him when they didn’t. And, on primary day, a 600-pound pig showed up at the Pelham polls.

More than other presidential campaigns, policy positions — even a candidates’ inconsistent policy positions — didn’t matter in New Hampshire this time around. Republican voters didn’t seem to mind Trump only registered as a Republican a few years ago. Similarly, Democrats didn’t care that Sanders still wasn’t technically a member of their party.

Instead, the New Hampshire primary was determined by economic populism and the varying size of its two fields. Once as large as 17 candidates, the size of the GOP field split Trump’s opposition, and allowed the unorthodox businessman to be the front-runner in every single poll of the New Hampshire primary since July.

For Democrats, a small field benefited Sanders. With US Senator Elizabeth Warren and Vice President Joe Biden taking a pass on mounting their own campaigns, Sanders could form a concrete coalition of economic progressives and Democrats who didn’t trust his opponent.

It was an easy argument against Clinton, who personally reaped the financial benefits of speaking to Wall Street bankers.

But the seeds of the Trump and Sanders populist candidacies were sewn even before April 2014. The Great Recession had served as a catalyst for revolt among the bases of both political parties, and the economic recovery that followed only amplified it. Tea Party movement supporters protested from the right, and the Occupy Wall Street movement protested from the left. Both existed long before Trump spoke in Manchester, or Sanders became a household name.

But on a Saturday in April nearly two years ago, two men took the torch from those movements. Sanders and Trump carried them through Tuesday’s primary, and likely much further and beyond.

James Pindell can be reached at james.pindell@globe.com. Follow him on Twitter @jamespindell or subscribe to his daily e-mail update on the 2016 campaign at www.bostonglobe.com/groundgame.