Marco Rubio suspended his presidential run after falling to Donald Trump in his home state of Florida on Tuesday, lamenting a political climate that rewarded anger over optimism.

"While we are on the right side, this year, we are not on the winning side," Rubio told supporters at rally near Miami.

He said the easiest way to win would have been playing to voters fears and anger. "But, that is not what’s best for America,” he said.

NBC News called the race just over an hour after polls closed, and within two hours of polls closing Trump had opened up a 19-percentage-point lead on the Florida senator. While every public poll since August had shown Rubio losing to Trump, the senator’s supporters held out hope for a last-minute surge in support in his home-county of Miami Dade.

But Trump siphoned off more than a fifth of the votes there, and even soundly defeated Rubio in many of the state’s more moderate-leaning counties, where the senator was hoping to at least break even with the frontrunner.

He hinted, however, that his presidential run wasn’t the end of his political career.

“I want you to know that I will continue every single day to search for ways for me to repay some solve this extraordinary debt that I owe this great country,” Rubio told a crowd of about 300 supporters on Florida International University’s campus.

His second-place finish in his home-state on Tuesday night capped a campaign marked by missed opportunities, false starts and squandered momentum. And it was a run defined — and perhaps derailed, allies said privately — by two key missteps: his New Hampshire debate gaffe, and his choice to attack frontrunner Donald Trump personally.

The first, in which he repeated himself multiple times in a moment decried by opponents as “robotic,” halted what had been strong forward momentum in New Hampshire in its tracks. The campaign’s internal polling had shown him working towards a strong second-place finish, but he ultimately finished fifth, giving Ohio Gov. John Kasich and Florida Gov. Jeb Bush’s campaigns legs.

Kasich’s continued ascent came back to haunt Rubio in a handful of Super Tuesday states, siphoning off enough support to prevent him from winning Virginia and making the delegate threshold in a handful of states.

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And his decision to go negative against Trump impacted one of his greatest assets in the race — his high popularity. Rich Beeson, Rubio's deputy campaign manager, said Rubio's popularity gave him an advantage over some of his other opponents.

"With [Texas Sen. Ted] Cruz, they talk about analytics and ground game all the time because they sort of have to have a different component to put them over the top because he’s not as likeable as Marco is," he said.

Rubio himself has admitted over the past week the personal attacks on Trump were a mistake, saying he wouldn’t do it again if he had the choice.

“My kids were embarrassed by it, and if I had to do it again I wouldn't,” he told NBC News last week.

It was also a campaign built on exceeding expectations — and when Rubio fell far short of expectations on Super Tuesday, his candidacy quickly collapsed. A top campaign adviser said the thing that hurt the campaign most was, simply, not winning. Rubio's failure to win states early on contributed to the collapse in his narrative as the most electable, anti-Trump candidate, making it harder to make up that lost momentum in each subsequent state.

That focus on expectations — on winning the media narrative, if not every primary contest — came as both a reaction to the candidate’s weaknesses and an effort to enhance his greatest assets. Rubio’s advisers knew that they’d never match the resources of some of the other campaigns, but that their candidate was perhaps the most rhetorically gifted and charismatic of any in the field.

They also identified early on that Rubio had no clear constituency — he had turned off many in the Tea Party set that helped elect him to the Senate in 2010 with his involvement in the 2013 immigration reform effort, but was still too conservative on policy for many of the upper-middle-class white voters that identified with the candidate personally.

So they sought to carve out a middle path — to be every voter’s second choice, maintain Rubio’s high popularity and outlast the rest of the field.

That lack of resources and clear-cut base drove a strategy focused on gaining maximum exposure in a handful of narrowly-focused media markets and congressional districts where the candidate had a clear constituency and an opportunity to win delegates. They focused largely on holding rallies and doing local interviews in suburban counties populated by upper-middle-class white voters who, they felt, identified with the candidate.

"There’s not a whole lot of people up on that debate stage...who had trouble paying student loans, who people in those collar suburbs can really relate to — with young kids, student loans, it’s a very unique profile," said Beeson.

"Yet in Marco, they see someone who is them."

Beeson also said that the rallies were, optically, a positive asset for the candidate. "The pictures showing these crowds...the crowds are getting bigger and bigger, and you can sense the momentum."

But the emphasis on media exposure came at the expense, in later states, of organization-building. Rubio narrowly missed the threshold to earn delegates in a handful of states; he also missed winning Virginia by just a few thousand votes. The bad news continued through last Tuesday, where Rubio won no delegates from the three states voting that day.

His operation in Florida, too, was lacking — the campaign opened up its first office just over two weeks before Election Day, and initially struggled to bring in volunteers at the outset.

That disappointing Super Tuesday night left the candidate hobbled heading into the final two weeks before the Florida primary. He was buried in an avalanche of bad press, both caused by and contributing to a speedy collapse in his support.

Rubio's political future now remains in doubt. Speculation about a potential vice-presidential run has grown in recent weeks, with some anti-Trump Republicans suggesting Rubio should join forces with Cruz to defeat the frontrunner. Though Florida law allows him to jump back into the race for his Senate seat, Rubio has said decisively he has no plans to do so.

Rubio is also considered a potential gubernatorial candidate in Florida in 2018. But on Tuesday night, he said he was leaving it up to God.

“God makes no mistakes. And he has things planned for all of us. And we await eagerly to see what lies ahead,” he said.