The chorus started at 10pm on Thursday in the dark sweaty depths of the Glastonbury silent disco. Just a low rumbling at first, it built into a loud roar with hundreds of festivalgoers singing, at the tops of their voices: “OH … JE-REM-Y COR-BYN.”

Glastonbury this year may boast appearances from the biggest acts in the world, Ed Sheeran and Radiohead among them, but judging by the T-shirts, flags and impromptu musical outbursts, the man of the hour is the Labour party’s 68-year-old leader.

Corbyn is due to make an appearance at the festival on Saturday afternoon, opening for the outspoken hip-hop duo Run the Jewels. It is in a stark contrast to last year, when the politician was forced to cancel a Glastonbury speech after the result of the EU referendum and questions about his future as party leader.

Heather Cuss, 33, from south London, said: “There’s always a community atmosphere at Glastonbury but this year it’s definitely all about Jezza. We’ve seen musicians playing with Corbyn necklaces and everywhere you walk you hear people break out into Jeremy Corbyn chants. Even bands from abroad have been giving him a shout out as they’ve clearly heard everyone going, ‘Jeremy Corbyn, Jeremy Corbyn,’ and they’re joining in.”

In the dance area Shangri-La on Thursday, the New York brass band were leading the crowds in the ‘Oh, Jeremy Corbyn’ chant and the giant sand sculpture near the park stage was of Corbyn riding on the back of a fox and chasing Theresa May through fields of wheat.

Play Video 0:20 Glastonbury crowd chant 'Oh, Jeremy Corbyn' at silent disco

The political antics continued into Friday, when a man dressed as Theresa May in a full red suit and wig was chased through the crowd at the bandstand by eight foxes, to riotous cheers.

“I’m not Corbyn’s biggest fan but he’s become this celebrity icon here,” said Lizzie Gibney, 33, who said that despite her doubts about Corbyn as a leader, she had been heartened by how he had revitalised the youth vote. “Getting out the young vote was an incredible achievement and energising that group of people who hadn’t been targeted by politicians before, and that’s what you really feel being here. Corbyn fever is genuinely everywhere you go.”

Olly, 24, was one of the many festival goers at Worthy Farm, near Pilton, Somerset, sporting a Corbyn T-shirt. “I’m wearing it because Corbyn has put Labour back to where it should have been,” he said. “I’m definitely going to see him talk and will probably do some chanting too.”

Indeed, it seems that this year politicians are the new rock stars. Former shadow chancellor Ed Balls, enjoying his first Glastonbury, was stopped for selfies every five minutes as he walked around Shangri-La and was met with shrieks of delight and songs everywhere he went, to the bemusement of his wife, Yvette Cooper, who hasn’t been to Glastonbury for 30 years.

Andrew Myors, 30, and Matt Foncette, 32, said they had been among those singing the Corbyn when one of the DJs played The White Stripes’ track Seven Nation Army – the backing music for the chant – and the whole field erupted into song.

Facebook Twitter Pinterest Ed Balls (3rd right) and his wife Yvette Cooper (2nd right) waiting in a queue for the showers. Photograph: Yui Mok/PA

“Coming here you realise how much of a phenomenon Corbyn is,” said Myors. “And it isn’t just one type of person who’s here and joining in these songs – he’s united all these people who come to Glastonbury to watch completely different genres of music. And it’s such a different vibe from last year. I definitely don’t think there were many people singing ‘woop Brexit’ chants at Shangri La.”

Friday’s headliners are Radiohead, who will be hoping for a slicker performance than their last Glastonbury appearance in 1997. The band described it as the “set from hell” after equipment broke and frontman Thom Yorke almost stormed off during the encore.

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Diehard fans travelled from all over the world, including Japan and Canada, for the set, and by 9am several groups had taken their places in front of the stage, 12 hours before the band were due to appear.

Mariko, 35, Yuriko, 31, and Hans, 25, who travelled from Tokyo and Colombia, were decked out in the Oxford band’s merchandise and armed with bags of food. Asked how they intended to last the day, Yuriko said: “No problem. I never go to the toilet.”

With the recent terror attacks and political uncertainty after the general election, the mood at Glastonbury was one of defiance and that, while the world outside the festival walls might be crumbling, the spirit of community and hedonism would not be tainted.

Lesley Wright, 62 and Shan Shanahan, 54, who have been friends for 15 years and live in the same village in South Wales, were at Glastonbury for the first time, with Wright’s husband who uses an electric wheelchair. The festival, they said, had always been on their bucket list.

Facebook Twitter Pinterest A sign reading ‘Jeremy Corbyn: acid house set’. Photograph: Alicia Canter/The Guardian

“I’ve been so overwhelmed by the spirit of this festival, it’s definitely something the world needs right now,” said Wright. “All coming together as a community, and speaking as one. It’s all ages, everybody is here, it’s amazing. With everything that’s going on, we should be coming together like this more than ever.

“Coming here with somebody with a disability is a feat in itself but I will tell you something, the facilities are amazing. We’re just going to go with the flow, just go and see who’s giving the good vibe.”