Hillary Clinton, the first woman to become a major party’s presidential nominee, endorsed Joe Biden’s White House bid on Tuesday, continuing Democrats’ efforts to coalesce around the former vice president as he takes on President Trump.

Clinton made her announcement during a Biden campaign town hall to discuss the coronavirus and its effect on women. Without mentioning Trump by name, Clinton assailed the Republican president’s handling of the pandemic and hailed Biden’s experience and temperament in comparison.

“Just think of what a difference it would make right now if we had a president who not only listened to the science … but brought us together,” said Clinton, who lost the 2016 presidential race to Trump. “Think of what it would mean if we had a real president,” Clinton continued, rather than a man who “plays one on TV.”

A little hint about who the surprise guest will be for @JoeBiden‘s 3pm ET town hall today:

(She’s excited.) pic.twitter.com/iGHo6a6G1s

— Hillary Clinton (@HillaryClinton) April 28, 2020

Biden, as a former vice president and six-term senator, “has been preparing for this moment his entire life,” Clinton said. “This is a moment when we need a leader, a president like Joe Biden.”

Former Secretary of State Hillary Clinton, shown in February, is expected to endorse former Vice President Joe Biden for the Democratic nomination for president. Markus Schreiber/Associated Press

With her historic candidacy, Clinton remains a powerful — and complex — figure in American life. Her 2016 campaign inspired many women, and her loss to Trump resonates to this day. The female candidates in the 2020 Democratic presidential primary often faced skepticism that a woman could win the White House.

Biden has pledged to select a woman as his vice president.

Having competed against Trump, Clinton could offer Biden unique insight as he prepares for the November general election. Her endorsement is the latest example of leaders from across the party’s ideological spectrum rallying behind Biden.

In recent weeks, the former vice president has picked up support from former President Barack Obama, House Speaker Nancy Pelosi and leading progressives such as Sens. Elizabeth Warren of Massachusetts and Bernie Sanders of Vermont. Hillary Clinton’s husband, former President Bill Clinton, has not yet publicly endorsed Biden and has kept a lower profile during the Trump era.

The swift unification around Biden stands in stark contrast to four years ago, when Hillary Clinton was unable to win over a significant portion of the electorate’s left flank. Sanders battled her to the end of the primary calendar and waged a bitter fight over the party platform before endorsing her and campaigning for her in the fall. Hillary and Bill Clinton have argued that Sanders’ push deeply wounded her campaign against Trump.

The Trump campaign sought to foment the same tension on Tuesday by arguing that the Democratic establishment is again asserting itself.

“There is no greater concentration of Democrat establishment than Joe Biden and Hillary Clinton together,” Brad Parscale, Trump’s campaign manager, said in a statement. “Both of them carry the baggage of decades in the Washington swamp and both of them schemed to keep the Democrat nomination from Bernie Sanders.”

Despite overlapping for decades as Democratic heavyweights, the Clintons and Biden have never been especially close allies. Biden’s nearest alignment with Hillary Clinton came during Obama’s first term, when Biden was vice president and Clinton was secretary of state. Both had sought the Democratic nomination in 2008 — and both were dogged by their 2002 votes as senators in favor of the war powers resolution that President George W. Bush used to invade Iraq in 2003.

Biden suggested in his 2017 book, “Promise Me, Dad,” that Obama favored Clinton’s 2016 presidential bid over the possibility of Biden running. With Obama by his side, Biden announced from the White House Rose Garden in 2015 that he wouldn’t seek the presidency the following year.

As first lady and secretary of state, Clinton was among the leading voices in women’s rights discussions around the world. She made headlines during her husband’s first term with forceful advocacy for women during a United Nations conference in Beijing, where the Chinese government was under fire for human rights abuses.

“I believe that, on the eve of a new millennium, it is time to break our silence,” Clinton said. “It is time for us to say here in Beijing, and the world to hear, that it is no longer acceptable to discuss women’s rights as separate from human rights.”

She punctuated her argument with a line that has been replayed and repeated countless times since: “Human rights are women’s rights, and women’s rights are human rights.”

Yet Clinton’s advocacy for Biden presents complications. After decades in the spotlight, she’s a polarizing figure who has been criticized for everything from her advocacy for health care reform in the 1990s to her decision to remain in her marriage following her husband’s affair with a White House intern.

Her presidential endorsement comes as a former Senate staffer has recently accused Biden of sexually assaulting her in the 1990s, when he was a senator from Delaware. Trump made Bill Clinton’s affairs an issue during the 2016 campaign despite his own indiscretions and allegations of sexual assault.

Biden campaigned for Hillary Clinton in the fall of 2016 and has praised her during his 2020 run as someone who “would have made a great president.”

But he’s also implicitly criticized her campaign by saying repeatedly that Democrats did a poor job of reaching white working-class voters who once helped anchor the Democratic coalition. As recently as an April 15 fundraiser, Biden touted his own ability to win “the kind of folks I grew up with,” the “high-school educated” population who believe Democrats have abandoned them.

And he regularly cites that slice of the electorate when arguing he can win Wisconsin, Michigan and Pennsylvania — the three states where Clinton’s narrow losses handed Trump an Electoral College majority despite her national popular vote lead.