Joe Biden hardly seemed to be sweating.

He was standing on a small wooden stage at the Iowa state fair, a large crowd around him, no shade in sight. He wore a dark polo and his signature aviator sunglasses, and spoke with a vigor that was absent in his first two Democratic debate performances. But while his audience perspired in the oppressive August sun, cooling themselves with paper fans, Biden seemed at ease.

“We really are in a fight to restore the soul of this country,” he said, to applause. “It’s time to remember who in God’s name we are.”

Biden, the current Democratic frontrunner for president, can be a gaffe-machine on the campaign trail. But at events like this, where his “Uncle Joe” folksiness fits right in, Biden seemed in his element – which is ironic, considering it was here, at the Iowa state fair in Des Moines, where his first campaign for president fell apart more than three decades ago.

Speaking at the fair in 1987, Biden was found to have plagiarized a huge chunk of his closing remarks from a speech by the British Labour leader, Neil Kinnock. The scandal killed his campaign; he dropped his bid for the 1988 Democratic nod a month after it broke.

But this time around Biden has appeared more robust – even as the blunders have kept coming. He has endured two rounds or mostly poorly reviewed debate performances, rode out a scandal over inappropriate touching of women, flip-flopped on abortion policy and committed numerous faux pas. Last week alone he got the place names of two mass shootings wrong and then inadvertently told a mostly minority crowd at an Iowa event: “Poor kids are just as bright and just as talented as white kids.”

Yet, entering the race as the presumptive frontrunner, Biden has comfortably led the field since – and even some of those who don’t support him view him as the inevitable nominee.

“I think he is the de facto strongest candidate,” said Alan Collinge, a Washington state native who attended Biden’s soapbox address but doesn’t see the former vice-president as his preferred choice.

Biden enjoys broad name recognition, access to a major donor network, and is beloved by the Democratic establishment. But that establishment increasingly seems to have fallen out of favor with the younger, more progressive wing of the party, which has sought fresher faces and more transformative ideas, and has challenged the idea that he’s the most electable candidate in the field.

He and his supporters have cast him as the most viable choice to defeat Donald Trump in 2020. But months into his campaign, with opponents making moves in the polls, should Biden really be as comfortable as he seems?

Jeanne Trachta, who came to the fair from Council Bluffs on the far west side of the state, is a farmer who has been hurting from Trump’s trade war. She’s “hanging in there”, she said, but is looking for relief – not just from the Trump’s trade policies, but from a presidency she says has been toxic for the country.

Ousting Trump is her main priority in 2020, and she will back the Democrat most capable of beating him.

Is that Biden?

“He came across pretty darn good today,” she said.

Trachta had initially backed Biden in the 2008 race, but she hasn’t made up her mind yet this time around. She liked Eric Swalwell, who in the first debate called on Biden to “pass the torch” to a new generation of Democrats, but he dropped out of the race early last month. She has some concerns still about the 76-year-old Biden, including his age. But, she said, he might be the best chance Democrats have to get rid of Trump.

“He’s good,” she said of Biden. “He’s experienced.”

Arla Darling agrees.

She had been a registered Republican, but quit the party over Trump.

Not far from the soapbox, a local radio station had set up a tent in which passersby could cast a corn kernel for the presidential candidate of their choice. Darling dropped a kernel in the Mason jar with Biden’s face on it. By 2pm, when Biden finished his speech, he was leading Democrats in the Cast Your Kernel poll with 34%; Elizabeth Warren was his next closest competitor, at 13%.

“I’d like to see somebody give [Trump] a good run,” she said.

But others in attendance raised concerns about his candidacy.

Collinge, who stopped by the fair to see the candidates during a cross-country road trip, held a Biden campaign sign as he left the speech, but doesn’t consider himself a supporter. He’s looking for a candidate who will address the student debt crisis, and hasn’t quite found one yet. He says progressives Warren and Bernie Sanders have put forth the “most attractive” plans to fix the issue – they have called for student debt to be canceled – but he’s not sure those ideas stand a chance on Capitol Hill.

Biden, Collinge said, is “actually one of the bad guys on this issue”, owing to his previous backing of bills that made it more challenging to reduce student debt. That and other aspects of Biden’s history make Collinge wary of him. And while he still feels Biden will probably get the nomination, Collinge believes he’s coasting on the “past glory” of the Obama administration.

Indeed, a strong sense of nostalgia animates Biden’s latest presidential campaign, and he often gives off the impression that everything in the country had been running smoothly until Trump came around.

Many progressives, though, see Trump not as an aberration, but a symptom of deeper problems that have existed in the country since long before he defeated Hillary Clinton.

Edward Rosson came from Kansas to see the candidates at the fair; nearly the entire field of Democrats, as well as the Republican Bill Weld, who is aiming to give Trump a primary challenge, converged on the fairgrounds to get their 20 minutes on the soapbox.

Rosson likes Biden and got a book signed by him, but would need to see drastic changes in his platform to support him over Sanders or Warren, who have impressed with their consistency and detailed policy proposals.

“I thought he was good,” Rosson said of Biden’s soapbox speech. “But he didn’t address any of the underlying issues.”

Democratic strategist Kelly Dietrich agrees that Biden has yet to “tie his built-up good will and credibility from the past to a vision of the future that is aggressive and progressive” to unify the party behind him.

Still, Dietrich suggested Biden may be right to feel comfortable.

“We can pull apart and nitpick every detail of debate performances, but the reality is the vice-president starts with inherent advantages that the other candidates simply don’t have,” Dietrich said. “Joe Biden’s challenge is to pair what people know about him already with an empowering, inspiring and aggressive vision for the future.”

“That is what I don’t think we have heard from him yet.”