The Obamas, the Clintons, Carter and even JFK: How the old gang is helping Kamala Harris

CHICAGO − Barack Obama, whose presidential prospects were launched by his virtuoso address at the Democratic National Convention two decades ago , delivered a passionate appeal on Tuesday night for the voters who propelled his rise then to work for his party's newest nominee now.

"Make no mistake: It will be a fight," Obama said, making the case for Kamala Harris to an audience in the United Center that gave him a tumultuous welcome. "For all the incredible energy we've been able to generate over the last few weeks, this will still be a tight race in a closely divided country − a country where too many Americans are still struggling and don't believe the government can help."

Donald Trump is a danger to the nation's fundamental values, he warned. "So let's get to work."

He and former first lady Michelle Obama weren't the only notables from the past speaking at the convention that in a rollicking roll call of the states Tuesday ceremonially nominated Harris.

This week's lineup in Chicago is a conspicuous display of unity in a political party so routinely described as "in disarray" that the phrase has become a mocking meme. Every living Democratic president is showing up in one way or another, representing tenures that stretch back five decades.

President Joe Biden spoke Monday , embracing Harris after reluctantly stepping back from the campaign . Former President Bill Clinton was set to speak Wednesday. In an animated speech Monday, Hillary Clinton predicted Harris would shatter the "highest, hardest glass ceiling" that she had managed to only crack as the 2016 nominee. Jesse Jackson, a groundbreaking presidential hopeful who is 82 and ailing, gave the audience a thumbs-up from his wheelchair on stage.

Even former President Jimmy Carter, 99 years old and in hospice care at his home in Plains, Georgia, relayed remarks to the United Center on Tuesday via his grandson. "My grandfather can't wait to vote for Kamala Harris," Jason Carter declared.

He was followed on stage by the grandson of former president John F. Kennedy, likening Harris to JFK. "Once again, the torch has been passed to a new generation," Jack Schlossberg said, "to a leader who shares my grandfather's energy, vision and optimism for our future."

Elections are about the future, of course, not the past, and there's a limit to what any endorsement can do to sway votes. Millions of today's voters were born after Bill Clinton, not to mention Carter, had moved out of the White House.

That said, no one rivals the star power and political clout of the Obamas, the two most popular figures in Democratic politics today. As the first Black president , he also knows something about the attacks a pioneering contender like Harris will face in the next 70-something days of this campaign.

The daughter of an Indian mother and a Jamaican father, she would be the first woman and the first person of Asian heritage to be president.

If she wins, that is.

20 years later, a tougher tone

Obama's words Tuesday in Chicago had a harder edge than the electrifying keynote address he delivered in Boston in 2004 at the convention that nominated Massachusetts Sen. John Kerry for president. (Kerry lost, but four years later Obama was nominated for the White House and won, twice.)

"There is not a liberal America and a conservative America − there is the United States of America," Obama, then an Illinois state senator, had declared to rising cheers in Boston. "There is not a Black America and a white America and Latino America and Asian America − there's the United States of America."

This time, his tone was tougher, and his warnings about Trump were ominous.

"This is a 78-year-old billionaire who hasn't stopped whining about his problems since he rode down his golden escalator nine years ago," Obama said. "It's been a constant stream of gripes and grievances that's actually gotten worse now that he's afraid of losing to Kamala."

But those tactics won't necessarily work, he said, "because the vast majority of us don't want to live in a country that's bitter and divided. We want something better. We want to be better. And the joy and excitement we're seeing around this campaign tells us we're not alone."

Michelle Obama, who got her own tumultuous welcome, delivered cautionary words, too.

At the 2016 convention, she had told the audience to claim the high ground when enemies attacked. "When they go low, we go high," she had said of that campaign, the first against Trump.

This time, she mocked him as a whiner and a cheater whose wealth and privilege had protected him from the consequences of his failures. She predicted he would wage a dirty campaign against Harris.

"It's his same old con," Michelle Obama said. "Doubling down on ugly, misogynistic, racist lies as a substitute for real ideas and solutions that will actually make people's lives better."

Meanwhile, back at the Fiserve Forum ...

When the roll call ended Tuesday, the Jumbotron at the convention showed a live shot of Kamala Harris and her running mate, Minnesota Gov. Tim Walz, as they entered a rally the campaign was holding less than 100 miles away in Milwaukee − at the Fiserv Forum, the arena where the Republican National Convention nominated Trump last month.

Video from the Chicago convention was shown on the Jumbotron in Milwaukee.

“We are so honored to be your nominees,” Harris said, vowing to wage "a people-powered campaign" and to return to the Chicago convention Thursday to formally accept the Democratic nomination.

The turnout of the party's leaders from the past stood in stark contrast to the Republican convention. Aside from Trump himself, not a single former Republican president or vice president or presidential nominee attended.

Not former president George W. Bush , or former vice presidents Dick Cheney and Dan Quayle, or former presidential nominee Mitt Romney. Not even Trump's own former vice president, Mike Pence.

That's understandable, given the hard feelings since Jan. 6 rioters, spurred by Trump's incendiary rhetoric, attacked the U.S. Capitol with cries to "hang Mike Pence" for his refusal to try to block the official counting of the Electoral College votes that would elect Joe Biden.

Ruth Bloch Rubin, a University of Chicago political scientist who studies political parties, suggested Trump might not be interested in having other leaders in the spotlight. "This is his show and always has been," she said − and the other GOP leaders might not want to be there, either. "It may reflect that many former Republicans stars would like to keep their distance from Trump, whether because they disagree with his policies or simply don’t want to play by his rules."

In the Democratic Party, the impetus for former officials to show up may be a reaction to Trump, too. One reason officials and rivals and activists have united so quickly behind Harris is a broad determination to deny Trump a second term.

"Whether they think he’s a threat to democracy or simply just weird, that’s got to be a powerful motivator," she said.

In Chicago, there have been protests outside the hall over Israel's treatment of Palestinians in Gaza since the Hamas attack on Israel last fall. But there have been no significant disruptions inside the arena, at least so far. Vermont Sen. Bernie Sanders, whose supporters disrupted the 2016 convention that nominated Hillary Clinton, on Tuesday delivered a full-throated endorsement of Harris.

Trump's agenda is the "radical" one, Sanders said, "and we won't let it happen."

This article originally appeared on USA TODAY: The Obamas, the Clintons, Carter and even JFK: How the old gang is helping Kamala Harris