In the final weeks of the 2016 campaign, then-President Barack Obama was a ubiquitous presence stumping for Democratic nominee Hillary Clinton, making her case as a worthy successor but also emphasizing that his own legacy was on the ballot.

Obama is back in the role of surrogate-in-chief for Joe Biden with 11 days left in the 2020 cycle, and though his message is not as pointed, the fate of the 44th president’s enduring impact on the nation is again in the balance.

President Trump has systemically sought to dismantle Obama’s policies and degrade his broad popularity, repeatedly leveling false attacks that the previous administration spied on his campaign. Last week, Trump promoted a baseless conspiracy theory that Obama and Biden had faked the killing of Osama bin Laden.

Limited by public safety concerns amid the coronavirus pandemic, Obama had until recently confined his activism to virtual fundraisers and targeted media hits. But he debuted on the campaign trail with a passion this week, delivering a punishing takedown of Trump’s presidency and personal character at a drive-in rally in Philadelphia on Wednesday.

Biden campaign aides said Obama will play a key role until voters go to the polls Nov. 3, with his tour continuing Saturday at a drive-in rally in Miami.

For Biden, the former president’s presence puts the Democratic Party’s most popular figure on the trail to rally key constituencies. Although Biden has made inroads with suburban voters, seniors and other moderates, he has struggled at times to energize young people, African Americans and Latinos.

Obama also feels fewer inhibitions than Biden to impugn Trump with red-meat attacks that appeal to the liberal base, as Biden aims his closing pitch at centrists and swing voters, people familiar with the campaign’s playbook said.

For Obama, another campaign against Trump offers an opportunity to settle the score by helping his former vice president topple him. Biden has pledged to quickly undo many of Trump’s policies and strengthen projects started under Obama, such as the Affordable Care Act, which Trump has sought to undermine.

Rep. Cedric L. Richmond (D-La.), national co-chair of the Biden campaign, said Obama is “reminding Democrats what’s at stake, reminding them of what he and Joe Biden accomplished.”

But he added that Obama’s forcefulness reflects a former president who will not be shy about “getting some things off his chest” about Trump in the waning days of the campaign.

Obama has plenty riding on the outcome. The first installment of his long-awaited autobiography of his White House tenure is set to be published next month, shortly after the election. The results of the 2020 race could go a long way to determine the extent to which his legacy is tied to Trump’s.

Obama aides said it was a mistake to frame his view of the election in such personal terms, suggesting that his urgency was based on a broader fear of what a second Trump term could do to the country’s basic foundations. Obama has pushed back on attempts from Trump to discredit voting by mail and has attempted to tie the mass social justice protests to the election, urging demonstrators to turn their anger and energy into power in the voting booth.

“He’s not focused on legacy. He wants to help make sure we save democracy,” said Eric Schultz, a senior adviser to the former president. “The stakes of this election are historic, given everything that’s on the line.”

The difference this year from 2016, Schultz added, “is that nobody needs to take our word for what a Trump presidency would look like. We are living it every day. We can look back at people’s experiences over the last four years.”

Trump has sought to appeal to younger Black and Latino men, whom his campaign believes could be attracted to the president’s tough talk and some policies he has pursued. At his debate with Biden in Nashville on Thursday, Trump touted his work on criminal justice reform and criticized Biden’s support of a crime bill in the 1990s that established harsh penalties for nonviolent drug crimes, which the former vice president has recently called a mistake.

“Nobody has done more for the Black community than Donald Trump,” the president said, prompting Biden to call him “one of the most racist presidents” in modern U.S. history.

Trump also took broad aim at Obama’s tenure, saying their administration had failed to produce results. “I ran because of Barack Obama, because you did a poor job,” he told Biden.

In a statement this week, Trump campaign communications director Tim Murtaugh suggested that Obama’s decision to wait until late in the Democratic primaries to formally endorse Biden was a sign of lackluster support of his former vice president.

In 2016, Obama bashed Trump in a stump speech that included hits that Trump’s critics still deploy — denouncing him for not releasing his tax records, puncturing his record as a business executive, mocking his Twitter beefs with pop culture figures.

In a speech in Miami five days before that year’s election, Obama took aim at Trump over the unearthed audio recording from a taping of “Access Hollywood” in which he spoke lewdly about assaulting women. “You want a voice who’s bragging about how being famous lets you get away with what would qualify as sexual assault, and calls women pigs, and dogs, and slobs?” Obama asked.

But Obama’s barnstorming of the country that fall often took on the feel of a farewell tour for his own nearly eight years in office — he drew large, adoring crowds and took to casting a Clinton presidency as, effectively, a third term of his own. Imploring African Americans to rally around her, Obama cast it in personal terms, telling the Congressional Black Caucus he would consider it a “personal insult” if they failed to turn out constituents at the polls.

“You want to give me a good send-off?” Obama told the group in September 2016. “Go vote.”

Former Pennsylvania governor Ed Rendell (D) said he senses a greater urgency among Democrats than four years ago, when Trump carried his state, which had voted for Obama in 2008 and 2012.

“The Obama people had the same problem the Democrats did and that is they were overconfident,” he said.

Despite Obama’s exhortations, turnout among Black voters in 2016 fell for the first time in 20 years, dropping to 59.6 percent after reaching a record-high 66.6 percent in 2012, according to a Pew Research Center study.

“No single politician has the ability to fully transfer what they can do when their name is on the ballot to somebody else,” said Brian Fallon, executive director of Demand Justice who worked as a spokesman on Clinton’s campaign.

Fallon called Obama an “extremely gifted communicator” and a major asset for any Democratic campaign. But he emphasized that “endorsements get excess credit when they work out. The idea that he couldn’t deliver Pennsylvania just shows his support is not 100 percent transferrable. That was true for Hillary and it will be true for Biden, too.”

Obama remains broadly popular. An NBC News/Wall Street Journal poll in August found 54 percent of Americans rated the former president positively and 34 percent negatively — far better numbers than Trump or Biden.

Aides said the former president has had to reassess the best ways to reach voters this year, given the restrictions imposed by the pandemic. Although Trump is continuing to hold large-scale rallies at airport hangars, Biden and his surrogates, including Obama, have opted for smaller-scale and virtual events.

In 2016, the Clinton campaign asked the Obama team to focus on six swing states — Ohio, Florida, Pennsylvania, North Carolina, Iowa and New Hampshire. But he also traveled to Michigan on the eve of Election Day, a sign that the Clinton team was nervous about Trump’s appeal in the Upper Midwest. Trump swept Michigan, Wisconsin and Pennsylvania en route to his upset victory.

This cycle, Obama has focused on get-out-the-vote efforts among more marginalized communities. He posted a video to social media demonstrating how to vote by mail by filling out his absentee ballot from Chicago on camera.

Four years ago, the night before the election, Obama and Clinton met up in Philadelphia for a mega-rally with Bruce Springsteen. Aides to Obama and Biden declined to disclose plans for the next 10 days, but they emphasized that the threat of the pandemic has made that kind of event unrealistic.

Former first lady Michelle Obama, who delivered an impassioned videotaped endorsement of Biden during the Democratic National Convention in August, has continued to promote him in video messages. But she is not planning the kind of in-person rallies she did in 2016 at the request of the Clinton campaign.

“We always talked in the White House that it’s not about the number or quantity of events,” said Jen Psaki, who served as communications director in the Obama White House. “It’s about the impact of the moment. That’s even more the case with [the virus]. If we were in a different universe where Trump was doing six events a day, maybe former president Obama and Michelle Obama would be doing more. But that’s not what’s happening.”