WASHINGTON (AP) — Former President Donald Trump has plans to radically reshape the federal government if he returns to the White House, from promising to deport millions of immigrants in the U.S. illegally to abolishing government agencies and firing tens of thousands of workers and replacing them with loyalists.

Liberal organizations in Washington are backing President Joe Biden and say they expect Trump to lose. But they’re quietly trying to install roadblocks just in case.

A collection of activists, advocates and legal experts is promoting new federal rules to limit presidential power while urging Biden’s White House to do more to protect his accomplishments and limit Trump in a possible second term. All of that is happening with far less fanfare than plans by Trump supporters to create a conservative government-in-waiting via an effort known as “Project 2025.”

The Office of Personnel Management, the federal government’s chief human resources agency, proposed a rule against reclassifying tens of thousands of workers so they can be more easily fired. According to spokesperson Viet Tran, the office will finalize the rule in April. That means that a future administration would likely have to spend months — or even years — unwinding it if they want to try to do so.

Those supporting the effort are open about its limits.

“My impression is the Biden administration is taking very seriously that potential threat and is trying to do things now,” said Michael Linden, a former executive associate director of the White House Office of Management and Budget under Biden. But he added, “Nobody should be under any illusion that there’s anything that this president can do in advance to prevent the next president from doing things that are very damaging, potentially catastrophically.”

“There isn’t any magic bullet,” Linden said.

The White House is reluctant to talk about a second Trump term before Election Day, as that would imply it has plans for if Biden loses.

Trump “is already telegraphing plays straight out of the authoritarian playbook — gutting the civil service of people he deems disloyal and plotting revenge on his political enemies,” said Kevin Munoz, a spokesman for Biden’s campaign. “There’s one way of stopping Trump’s dangerous and un-American plans: reelecting President Biden.”

Still, Norm Eisen, who was chief ethics counselor to President Barack Obama, wants Biden to issue executive orders that could limit the use of the military domestically. Trump has talked about sending troops to the southern border or to Democrat-run cities dealing with rising crime rates.

“I understand the potential reluctance to signal any risk here as a political matter and that’s not an illegitimate consideration,” said Eisen, a senior fellow in governance studies at the left-leaning Brookings Institution. “But there are countervailing considerations given the threat that we face.”

Central both to Trump’s plans and the Democratic efforts to impede him is deciding how many government workers can be removed by a new administration, potentially to be replaced with loyalists.

Trump at the end of his term sought to reclassify thousands of the more than 2 million federal employees, stripping them of job protections and making them at-will employees under a new classification known as “Schedule F.” Around 4,000 federal employees are now considered political appointees who typically change with each administration. Creating Schedule F could have increased that more than tenfold.

Biden revoked that order but Trump says he’ll revive it should he win. And conservatives preparing thick policy books are strategizing on how to fire employees to make more room for Trump appointees.

A spokesman for Trump’s campaign did not answer a message seeking comment and the Heritage Foundation, which is running “Project 2025,” declined to answer written questions. But Heritage’s president, Kevin Roberts, told The New York Times Magazine that he wants to see “destruction” in the government.

“People will lose their jobs. Hopefully their lives are able to flourish in spite of that,” Roberts said. “Buildings will be shut down. Hopefully they can be repurposed for private industry.”

The OPM in September proposed the rule making it more difficult to reclassify employees and allowing anyone moved into a potential “Schedule F” to retain their protections against being fired.

It’s been endorsed by 27 advocacy organizations whose policy interests don’t always align.

“I think you’ve seen the federal agencies, and the president himself, talk about the importance of a functioning government, the importance of a democracy and the importance of a government that works for all people,” said Skye Perryman, president of the advocacy group Democracy Forward, which has been a leading proponent of the proposed rule.

James Sherk, a former Trump administration official now working at the America First Policy Institute, another group strategizing for a second Trump term, opposed the rule in a letter sent to OPM. Sherk argued worker protections against termination “enable what are typically very liberal career staff to stymie conservative policies.”

“The federal workforce has ideologically polarized, and this rulemaking would impede the ability of presidents whose views differ from the bureaucracy’s to implement their agendas,” Sherk wrote.

Many liberals are also promoting a separate OPM rule that could slow future executive branch orders to relocate government agencies. That grew out of the Trump administration’s announced plans to relocate agencies within the Department of Agriculture from Washington to Kansas City in 2019, and within the Bureau of Land Management from Washington to Grand Junction, Colorado, the following year.

Besides taking time to undo, federal rules can also be the basis for lawsuits — hundreds of which were filed to stop Trump priorities on issues ranging from immigration to the environment during his presidency.

Congress has also passed changes responding to issues that arose during the Trump administration. Lawmakers barred presidents from unilaterally withdrawing the U.S. from NATO and strengthened the Electoral Count Act, which Trump tried to put to the test on Jan. 6, 2021, when he pressed lawmakers to reject electors from states he lost on the basis of falsehoods he spread about voter fraud.

Advocates say Biden has more options to thwart a Trump administration, from promoting expanded collective bargaining agreements with federal personnel to beginning the complicated bureaucratic task of designating more government posts as policy-dedicated, thus making workers harder to fire.

“A lot of this about good governance,” said Ben Olinsky, senior vice president for structural reform and governance at the Center for American Progress’ Action Fund, the political arm of the Washington think tank. “If you believe in a functioning government, then you should want to use these tools to enshrine policy and make sure there’s continuity from one government to another, regardless of who you think might or might not be in the White House in a few years.”