Former Secretary of State Hillary Clinton endorsed Joe Biden’s campaign for the presidency Tuesday. 

But many Democrats believe Clinton offers a salutary lesson about the mistakes the former vice president must avoid, rather than giving any significant boost to his campaign.

Virtually no one in Democratic circles sees Clinton’s endorsement as having any real downside. But many have doubts about whether she can expand Biden’s appeal in a meaningful way. 

Given that both the 2016 nominee and Biden are pillars of the center-left Democratic establishment, there is assumed to be a high degree of crossover between their supporters already.

“There is no Democratic voter that is ideologically aligned with Hillary Clinton who isn’t already ideologically aligned with Joe Biden,” said Jonathan Tasini, a Democratic strategist who has supported Sen. Bernie Sanders (I-Vt.) in both his runs for the presidency.

The Clinton endorsement did, at least, provide a headline-grabbing moment for Biden, who has been marginalized on the public stage both by the coronavirus crisis itself and by the consequent impossibility of campaigning in a normal way.

Biden and Clinton, speaking on video links from their respective homes, lavished praise on each other Tuesday. 

Biden introduced Clinton as “the woman who should be president of the United States right now.” Clinton spoke of how Biden had been “preparing for this moment his entire life” and talked about the warmth of their personal relationship going back to the 1990s, when she was first lady and Biden was a U.S. senator representing Delaware.

The relationship has had its complications, however. Biden publicly mulled his own 2016 presidential bid at a time when he was the incumbent vice president. He stepped back, partly because he was still grieving the loss of his son Beau, who died of brain cancer in 2015. There was also a widespread perception that then-President Obama favored Clinton’s chances over Biden’s.

Biden has at times found fault with the Clinton campaign, in particular arguing that it was not closely enough attuned to the concerns of working people.

Biden’s 2020 campaign has already been built in one way to contrast with Clinton’s 2016 effort. A near-constant refrain from Biden allies is that he is best placed to win the key states of Michigan, Pennsylvania and Wisconsin.

Clinton lost all three states in 2016, becoming the first Democratic presidential candidate to lose any of them since the 1980s. 

Biden’s working-class roots in Scranton, Pa., and a more general sense that he is culturally in step with voters in those states fed into an electability argument that has helped him become the near-certain Democratic nominee.

Some on the left of the party insist that grassroots enthusiasm for Clinton was not as high as it could have been in 2016 and that Biden needs to make sure he is different. 

Charles Chamberlain, the chairman of the progressive group Democracy for America, argued that one of the key errors of the Clinton campaign came in “taking progressives for granted.”

He added, “In 2016, a lot of the focus of the Clinton campaign was on getting Republicans on their side. They did that entire campaign on the myth of a centrist Republican voter, and the reality is ... what happened? Joe Biden should not be following in that path.”

Chamberlain argued that one way Biden could reassure progressives would be via his choice of running mate: Sen. Elizabeth Warren (D-Mass.) and former Georgia gubernatorial candidate Stacey Abrams (D) were the two names he mentioned. 

Skeptics of Clinton point not just to her loss in the 2016 election but also to her public image, which remains divisive. 

Opinion polls have asked about her rarely since the 2016 election, but when they have, the results have been tepid at best. In a Gallup survey in mid-2017, she was viewed favorably by 41 percent of adults but unfavorably by 57 percent.

Defenders of the former secretary of State point to the fact that she received more votes in 2016 than President Obama did four years earlier.

She also has enormous fundraising prowess, which could prove useful to Biden, who lags behind Trump badly in that regard.

Most importantly, Clinton has intense support among many women, not least because of her status as the first female presidential nominee of a major party. 

Whether that popularity is transferable to Biden remains to be seen.

That issue is particularly germane right now because of new attention being given to claims from a former Biden staffer, Tara Reade, that the then-senator sexually assaulted her in 1993.

The Biden campaign has adamantly denied Reade’s story, and reporting by The New York Times, The Washington Post and The Associated Press has suggested that the evidence is inconclusive.

On the other hand, Reade’s account was given added impetus in recent days when Business Insider interviewed a former neighbor. The neighbor, Lynda LaCasse, says she remembers discussing the alleged assault with Reade in the years soon after it is purported to have taken place. 

LaCasse emphasized that she herself hoped Biden would win this year’s presidential election but also said, "This happened, and I know it did because I remember talking about it."

Political insiders think it noteworthy that Clinton and Speaker Nancy Pelosi (D-Calif.) have both chosen this week to endorse Biden — a high-visibility show of support as the pressure from the Reade matter builds.

“The timing is the real question we have to wonder about,” Chamberlain said.

Beyond that, however, there is a sense among many in the Democratic Party that, when it comes to Clinton, the times have simply moved on.

Clinton is “old news,” said Democratic pollster Paul Maslin. “I mean, Elizabeth Warren matters, Bernie Sanders matters, Barack Obama matters, Biden’s VP choice will matter, but Hillary Clinton is done, through, over.” 

The Memo is a reported column by Niall Stanage, primarily focused on Donald Trump’s presidency.