Bernie Sanders may have another chance at becoming a presidential nominee, but there’s a catch: He would have to join the Green Party.

Dr Jill Stein, the likely nominee for the progressive third party, told The Guardian that she is willing to offer the Vermont senator her slot on the ticket if he wanted to continue his “revolution”.

“I’ve invited Bernie to sit down explore collaboration – everything is on the table,” Dr Stein, a former Massachusetts physician and environmental-health advocate, said. “If he saw that you can’t have a revolutionary campaign in a counter-revolutionary party, he’d be welcomed to the Green party. He could lead the ticket and build a political movement.”

Dr Stein added that an “overwhelming” number of Sanders supporters have been flocking over to Green party events since Hillary Clinton clinched the Democratic nomination in June.

In pictures: US Elections 2016 Show all 15 1 /15 In pictures: US Elections 2016 In pictures: US Elections 2016 Democratic U.S. presidential candidate Bernie Sanders speaks to supporters after rival candidate Hillary Clinton was projected as the winner in the Nevada Democratic caucuses Reuters In pictures: US Elections 2016 Democratic presidential candidate Hillary Clinton takes photos with workers at her campaign office in Des Moines, Iowa AP In pictures: US Elections 2016 Republican presidential candidate Mike Huckabee, second from left, prays before lunch with supporters at Drake Diner in Des Moines, Iowa Reuters In pictures: US Elections 2016 Democratic presidential candidate and former Maryland Governor. Martin O'Malley, speaks during a campaign stop in Waterloo, Iowa AP In pictures: US Elections 2016 Democratic presidential candidate Bernie Sanders speaks, as his wife Jane O’Meara Sanders looks on, at a campaign event at Iowa State University Getty In pictures: US Elections 2016 Republican presidential candidate Marco Rubio speaks at St. Ambrose University in Davenport, Iowa Reuters In pictures: US Elections 2016 Republican presidential candidate Ben Carson speaks at a campaign event at Fireside Pub and Steak House in Manchester, Iowa. Getty In pictures: US Elections 2016 Republican presidential candidate Rick Santorum visiting supporters at a house party in West Des Moines, Iowa Reuters In pictures: US Elections 2016 Republican presidential candidate Donald Trump at a campaign event in Cedar Rapids, Iowa AP In pictures: US Elections 2016 Republican candidate Ted Cruz campaigns at Greene County Community Centre in Jefferson, Iowa AP In pictures: US Elections 2016 Senator Rand Paul speaks during a Caucus rally at his Des Moines headquarters in Iowa Getty In pictures: US Elections 2016 Republican candidate Jeb Bush speaks at a campaign event in Des Moines, Iowa AFP In pictures: US Elections 2016 Former Alaska Governor Sarah Palin introducing the arrival of Donald Trump during a campaign rally in Cedar Rapids, Iowa Reuters In pictures: US Elections 2016 A portrait of Democratic candidate Bernie Sanders at his campaign headquarters in Des Moines, Iowa Getty In pictures: US Elections 2016 Campaign badges on sale ahead of a Trump rally at the Ramada Waterloo Hotel and Convention Centre in Waterloo, Iowa Getty

“If he continues to declare his full faith in the Democratic party, it will leave many of his supporters very disappointed,” she said. “That political movement is going to go on – it isn’t going to bury itself in the graveyard alongside Hillary Clinton.”

The Green Party was established in 1984 and has been included on every presidential ticket since 1996, when consumer advocate Ralph Nader was its candidate.

“To be effective, a Green political organization must originate from a broad base of support, from natural allies concerned with ecological politics and social justice, peace and nonviolence, local and regional self-management, and grassroots democracy,” the committee’s original mission states on the party’s website.

Many of their political platforms are consistent with Mr Sanders’, particularly when it comes to campaign finance reform, universal healthcare, relieving student debt, and supporting a living wage.

Mr Sanders has not responded to Dr Stein’s olive branch at the time of this writing.

The millions of young voters who support Mr Sanders would certainly give the Green party the boost it needs in order to be included in televised debates alongside the Republicans and Democrats. As it stands, the Green party would need at least 15 per cent in polling to do so. Dr Stein currently has 4 per cent according to the latest Reuters/Ipsos poll.

Bernie Sanders says he'll vote for Hillary Clinton

But the unpredictability of the 2016 elections so far leaves Dr Stein feeling confident.

“I’m not holding my breath but I’m not ruling it out that we can bring out 43 million young people into this election,” she said. “It’s been a wild election; every rule in the playbook has been tossed out. Unfortunately, that has mainly been used to lift up hateful demagogues like Donald Trump, but it can also be done in a way that actually answers people’s needs.”

On the presumptive Democratic nominee, Dr Stein is not so sure young voters will flock to Hillary Clinton, especially if they still back Sen Sanders.

“[Clinton] is the fracking queen,” she said. “We would be fools to expect Hillary to deal with the climate crisis – the day of reckoning will come closer with her as president. As scary as Trump talks, Hillary has a scary record for warmongering and the neoliberalism.

“It’s a mistake to think the lesser of two evils will fix things. A lot of people are in the target hairs of a neoliberalist nightmare. Wars are bankrupting us morally and financially.”

Dr Stein’s website boasts that she earned a record number of votes for any female presidential candidate in the general election, at 470,000 – a record Ms Clinton is certain to break come November.

But a Clinton presidency will not be the answer to all of the problems Americans face, she believes.