MANCHESTER, N.H. — Bill de Blasio runs American's biggest city, oversees a budget bigger than Ireland’s, and commands a police force larger than the army George Washington needed to win America’s independence at Yorktown.

But right now, all the mayor of New York City needs is something much more humble — and, so far, elusive: a measly bump in the polls, from 1 to 2 percent.

“Look, I've been at 1 percent, like, 10 times,” he said while waiting backstage for his turn to be number 15 of 19 presidential candidates to address a gathering of New Hampshire Democrats last weekend. “This is what’s so tantalizing and aggravating about this. Just go up one more percent and you're in.”

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De Blasio is one of eight candidates in the Democrats’ bloated 2020 presidential field who have been more or less left for dead because they failed to qualify for Thursday’s debate after falling short of the 2 percent polling threshold.

“We at least know looking at that stage that the nominee will emerge from that group,” said Pete Buttigieg, the mayor of a city about 84 times smaller than New York — South Bend, Indiana — who did make the stage.

If you read what people say about de Blasio online (he says he doesn’t), you might wonder if he’s a glutton for punishment. “We're all humans. You're going to feel negativity and all of its forms,” he said.

But like a gambler convinced their luck is about to change, de Blasio and his fellow extra-long shots keep showing up because every speech is another pull of the lever, every interview another deal of the cards, and every trip to an early state another chance to catch the Moment That Changes Everything.

“An hour from now, one of those special moments could happen,” de Blasio said. “I'm not meaning that to be like believing in magic. I'm just saying, we just don't know. So the way you maximize the chance for that is to keep staying out there and saying what you believe.”

Spoiler alert: It didn’t happen.

But, hey, there’s another candidate cattle call next week. And there’s another debate coming up soon that he still, maybe, has a shot of qualifying for. He’ll reassess by Oct. 1.

“The odds are clearly against me,” he conceded. “But the odds have been against me in every election I've been in, and I've managed to prevail.”

Of course, one man's dream is another man’s delusion.

We tend to make movies about people overcoming the odds and proving the naysayers wrong, even though, according to the math, most people do not beat the odds.

And the kinds of people who get into politics, and especially the ones who think they should be in charge of the nuclear arsenal, tend to think the movie is about them. After all, they’ve all already hit the jackpot by making it the upper echelons of politics or business despite plenty of people telling them they were crazy along the way.

Still, most will end up as background characters in someone else’s against-all-odds story of this election.

And voters' patience for the dreams may be wearing thin. A majority of Democrats say the 10 candidates on stage Thursday are already too many. Just 3 percent want more, according to a new Politico/Morning Consult survey.

So how do you keep going when all the evidence tells you to stop? NBC News asked these candidates just what gets them out of bed in the morning, when plenty of Democrats would be happy if they stayed there. Turns out, there are a few simple rules of survival:

1. Stay positive

Tim Ryan is an optimist — “at a clinical level,” he joked over beer and escargot at a Manchester restaurant packed with political medium wigs, such as Jimmy Carter’s former finance guy and the mayor of a New Jersey town.

“You have to be,” Ryan, an Ohio congressman, said. “There are too many hurdles, there are too many tough days, but it’s a choice.”

The background of his iPhone was a quote from Joel Osteen, the celebrity televangelist pastor, about destiny. It began: “This is your time. This is your moment.”

He was missing his son’s football game to be here, which clearly pained the former high school quarterback who went into every game convinced he would win, and is now convinced he has the best chance of beating President Donald Trump.

The polls don't necessarily agree. So why keep putting himself through this?

“Because people always tell you why not to do something,” Ryan said. “There are always a million reasons why not to do something. But I would much rather be in the position of following my own instincts, my own heart, even if didn’t work out, as opposed to listening to some dumb bastard who didn’t know what they hell they were talking about. And if I didn’t take my chance, wondering what could have been?”

2. Be serious about your message

Aside from money — which is, of course, a real concern — the other major limiting factor on a presidential candidate’s ability to stay in the race when things aren’t going well is his or her ability to absorb Chernobyl-level doses of public humiliation.

Tom Steyer, the billionaire former hedge funder who has pledged to spend $100 million of his own money on his campaign, doesn’t have to worry about money.

"Do I take it personally?" Steyer paused, reflecting on the online mockery of his campaign. “No ... I'm doing it for a reason. I'm not wondering about whether I'm right about that reason. I think it's really important. So I'm not going to be deterred."

Steyer insists this is fun — at least, the talking to voters part — even though most people with his kind of wealth would rather use it to be on a beach in Fiji sipping a Mai Tai than getting grilled by reporters in their own suite at a DoubleTree in Manchester.

“If I were in Fiji sipping a Mai Tai, I would be despondent,” he said.

OK, so maybe he's not a beach guy. What about his 1,800-acre cattle ranch on the beautiful California coast?

"There is nothing to do there except work. Seriously, there's no recreational activities,” he said.

He ended up making the October debate stage after missing it in September, so his non-Fiji vacation will have to wait.

3. "Go where you're loved"

"The key to success is, stay off Twitter and be with voters. Go where you're loved,” author Marianne Williamson said. "Any time I get whiny, I slap myself across the face.”

Indeed, nearly every candidate said they don’t read their own press clippings. And they can all recall a particular voter who came up to them with an encouraging message and finding succor in that interaction for days or weeks to come.

Still, Williamson acknowledged she has to fight the urge to respond to detractors and was recently outed DMing the author Erica Jong to complain about her daughter Molly Jong-Fast’s criticism of Williamson online.

"You need a lot of emotional and psychological discipline to run for office,” Williamson said. “There are days you wake up and hope not to see your picture" in the news.

And maybe don't watch the debate.

Supporters of Hawaii Rep. Tulsi Gabbard held signs outside the New Hampshire Democratic Party Convention urging attendees to "seek alternative media Sept. 12," the day of the debate in which she was not included.

Would she be tuning in? "We’re still working that out," Gabbard said as she walked away.

4. Remember to find some "me time"

Running for president is hard. There are flight delays and missed family time. The pool of people who feel comfortable yelling at you about politics has expanded from just constituents to the entire country — everyone. And you can’t please everyone.

“If you want to feel good about yourself all the time, get a dog,” said Montana Gov. Steve Bullock as he looped through the hallways underneath the arena stands where New Hampshire Democrats stood waving opposing candidates’ signs (he didn’t really have any).

When he ended up on the same flight as Sen. Amy Klobuchar of Minnesota out of New Hampshire later that night, even American Airlines seemed to understand the dynamics of the race, placing him in the back while she got to sit in the first row of coach. (Klobuchar qualified for the debate on Thursday, while Bullock did not.)

“What keeps me grounded or reinvigorated is getting like that hour of alone time to go running,” said Bullock, who has run 14 marathons.

He was late to a big Iowa candidate event in June because he had run the Governor’s Cup half-marathon in Montana earlier that day. He came in 23rd, in a time of 1:46:03.12.

“Any day that I’m not having fun, it's my own fault. Right?” he said. “Like, I don't have to do this. It's just the future of representative democracy at stake.”

5. Get creative

If the media won’t cover your stump speeches, get creative.

Ryan dropped a Spotify album on which he talked about his policy platform. Bullock wrote a listicle of Dad jokes for Buzzfeed. Colorado Sen. Michael Bennet scored an endorsement from Gary Hart, one of those rare losing presidential candidates who got a consolation prize of helping to change his party's direction.

De Blasio found an unlikely ally in Fox News host Tucker Carlson when he appeared on Carlson's show last week to talk about his “robot tax” two days after Carlson called him the worst mayor in New York history. “I am completely with you on that one right there,” Carlson said.

6. Find meaning in the loss

“It's easier now than when it happened,” John Delaney said, reflecting on being booed for criticizing "Medicare for All" at the California Democratic convention in June in San Francisco.

Sure, Delaney, a former congressman from Maryland, would love to be the nominee. But as Sen. Cory Booker of New Jersey and his much larger entourage brushed by him in a hallway, Delaney was candid about how he sees his purpose in the race.

“I really do believe when I stood on stage in San Francisco and said ‘Medicare for All is a bad policy and bad politics,’ and I was booed, I really do believe that started to change the debate on that issue. And I’m happy about that,” he said.

Delaney, who is financing his own campaign, said he’ll say in through at least the Iowa caucuses in February.

“I am gratified that I changed the debate,” he said. “That has been in many ways a very positive thing for me personally in terms of my headset, because you actually start seeing tangible results.”

At least, in some areas. “It may not be in the polls,” he added.