Four years ago, Vermont Sen. Bernie Sanders started small in New Hampshire, but ended up winning the state's presidential primary big.

In the 2020 race, Sanders entered the Democratic primary as a top contender, and nothing - not the huge field, not other candidates adopting his key policy proposals, not even a heart attack - has changed that.

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Sanders’ resilience puts him in a strong position as voters here start seriously weighing their choices. Talk to voters at Sanders rallies these days and you can find plenty who share the view that that resilience is what will lead him to victory in New Hampshire again.

"I’m excited about Bernie Sanders because I believe in him," said Andrew Menard of Portsmouth. "He is real; he is steadfast. His message has been consistent for decades.”

Menard, who was at a Sanders rally at Southern New Hampshire University last week, runs a family creamery business and was buying a Sanders T-shirt bearing the slogan “Solidarity Forever.”

He thinks Sanders would have beaten Donald Trump in 2016, and says Democrats need him to be their nominee in 2020.

“Nothing changes my vote for Bernie Sanders,” Menard said.

Attracting voters like Menard - middle-aged and affluent - tends to be crucial to winning Democratic campaigns here. But so does winning the support of voters like Erica Therrien, a single mom of two without a college degree who now drives an Uber.

“I have, like, no liberal friends," she says. "It’s literally like a battleground between my family and friends about this, and they swear that he could never win and all this, but Bernie is the most anti-establishment, anti-corrupt government, like, for-the-people person and that’s what makes me so excited," Therrien said.

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UNH political scientist Dante Scala says Sanders may be the Democrat best equipped to pull support across a wide demographic spectrum this primary. His favorability numbers are consistently high across age and gender, and that places Sanders in the somewhat odd place for a candidate who’s spent a career calling for a political revolution: as perhaps Democrats' best hope at unity.

“Whereas (Joe) Biden is weak among well-educated voters, and (Sen. Elizabeth) Warren has some problems with less-educated voters," Scala said. "Maybe Sanders, oddly enough, could be the one to build across lines of age, education and social class.”

Voters, of course, will decide that. They still have plenty of time to make up or change their minds.

But Burt Cohen, an early Sanders backer in New Hampshire in 2016 who now sits on the campaign’s 2020 steering committee, says regardless of how things shake out for Sanders on Primary Day, he has put himself and his ideas at the center of the party’s identity.

“It's not him versus the establishment; it’s certainly not an insurgency this time," Cohen said. "And we all have to think about: Who can beat Trump? How can we inspire people, get people passionate?”

Of course, that’s the question every presidential campaign is now asking.