Eight youth-heavy progressive groups challenged former Vice President Joe Biden to adopt a host of left-leaning policy stances in order to earn the support of the young voters who overwhelmingly supported Sen. Bernie Sanders (I-Vt.).

The organizations ― including Justice Democrats, which backs primary challenges against moderate Democratic incumbents, and the youth-focused NextGen America, which is funded by liberal billionaire Tom Steyer ― laid out their demands in an open letter to Biden shortly after Sanders withdrew from the Democratic primary on Wednesday.

Together, the groups promise to spend more than $100 million helping turn out young voters in the coming general election, but they warn that those funds will be less effective if Biden does not accommodate young voters’ policy preferences.

“Messaging around a ‘return to normalcy’ does not and has not earned the support and trust of voters from our generation,” write the progressives groups, which also include the gun safety-focused March for Our Lives Action Fund, the IfNotNow Movement to end the Israeli occupation, the Sunrise Movement for climate action, the immigrant rights group United We Dream Action, Student Action and Alliance for Youth Action. “For so many young people, going back to the way things were ‘before Trump’ isn’t a motivating enough reason to cast a ballot in November.”

“We are uniquely suited to help mobilize our communities, but we need help ensuring our efforts will be backed-up by a campaign that speaks to our generation,” the groups added.

The likelihood that Biden adopts the groups’ ambitious demands varies greatly from one proposal to the next.

The assembled groups ― some of which, like Justice Democrats, are run by younger adults, but do not explicitly target or mobilize young people ― want Biden to sign on to “Medicare for All,” empower the federal government to manufacture generic drugs, back tuition-free public college, get behind a wealth tax, fight to enact a $10 trillion green infrastructure bill capable of making the country’s energy use 100% renewable by 2030, endorse rolling back decades of tougher immigration enforcement, work to halve the country’s incarcerated population, set a goal of halving all national deaths by gun violence, require congressional authorization for any war, as well support the abolition of the filibuster and the expansion of the Supreme Court.

The Democratic Party’s last presidential nominee failed to mobilize our enthusiasm where it mattered. We can’t afford to see those mistakes repeated. Progressive groups' open letter to former Vice President Joe Biden

The letter also features detailed suggestions for how Biden should staff his administration in order to govern in a progressive fashion.

The coalition of groups recommends that Biden appoint elected officials who endorsed either Sanders or Sen. Elizabeth Warren (D-Mass.) as leaders of his transition team, such as Democratic Reps. Ro Khanna and Katie Porter of California, Pramila Jayapal of Washington state and Ayanna Pressley of Massachusetts. They are asking Biden to pledge not to appoint Wall Street executives, corporate lobbyists or any individuals associated with the fossil fuel, health insurance or private prison industries to any roles in either his transition team or his administration itself.

Instead, they want Biden to task a “trusted progressive” with running the White House office in charge of hiring. The organizations are encouraging him to break with the recent Democratic presidential tradition of hiring economic advisers from the business-friendly establishment, and draw from a brain trust of more liberal economists, legal experts, labor leaders and health policy specialists.

Biden, now the presumptive Democratic presidential nominee, is his party’s second consecutive standard-bearer to win despite a lack of support from younger voters, who generally skew more liberal in their views. Sanders bested Biden among voters under 30 by significant margins, even in states like South Carolina, where Biden trounced the Vermont senator.

MANDEL NGAN/AFP/Getty Images Former Vice President Joe Biden, seen here participating in the March 15 debate with Sen. Bernie Sanders (I-Vt.), now faces the task of uniting the Democratic Party behind him.

The urgency around pushing Biden to the left ― an unusual move for candidates who have historically sought to project a more moderate image in the general election ― reflects a desire by progressive groups to avoid the apparent mistakes of the 2016 cycle.

Hillary Clinton, who defeated Sanders for the Democratic nomination in 2016, adopted a more progressive college aid proposal afterward. But critics cite her failure to ignite youth turnout as a major reason she ended up losing to Donald Trump in November 2016.

“The victorious ‘Obama coalition’ included millions of energized young people fighting for change,” the authors of Wednesday’s open letter write. “But the Democratic Party’s last presidential nominee failed to mobilize our enthusiasm where it mattered. We can’t afford to see those mistakes repeated.”

It is virtually unthinkable that Biden will accede to every last one of the coalition’s demands. For example, he has made his opposition to Medicare for All a staple of his candidacy.

But in other respects, he has already proven more pliable. After Warren’s withdrawal in early March, he adopted a bankruptcy reform proposal very similar to hers, effectively reneging on his leading role in the passage of 2005 legislation making it harder to declare bankruptcy. And he has also embraced the proposal Clinton backed in 2016 to make public college tuition-free for families earning less than $125,000.

Ben Wessel, a spokesman for NextGen America, said that his group and its allies still want to see more from Biden in terms of climate action, pro-democracy institutional reforms and measures to close the income and wealth gaps.

“He’s started making movements in the last few months, but there’s still room to grow,” Wessel said.