CHICAGO — As he did in his first speech to a Democratic National Convention 20 years ago, former President Barack Obama emphasized the connections binding Americans together and called for a more positive national atmosphere on the second night of this year’s convention Tuesday, while rallying Democrats to campaign for Vice President Kamala Harris.

At the United Center, in a convention hosted by their hometown, Obama and former first lady Michelle Obama, who spoke immediately before the former president, scattered references to the 2008 and 2012 White House races he won as they made the case for Harris.

“America, hope is making a comeback,” Michelle Obama said, referring to the theme of her husband’s 2008 campaign and tying it to Harris.

The energy among the Democrats since Harris became a presidential candidate a month ago could be described as “the contagious power of hope,” she said.

The couple also trained criticism on Republican nominee former President Donald Trump, painting him as an agent of division and calling for voters to reject him in favor of a more inclusive nation.

“Donald Trump wants us to think that this country is hopelessly divided between us and them,” Barack Obama said. “Between the real Americans, who of course support him, and the outsiders who don’t.”

He called for Americans to turn aside that point of view.

Republicans in their response also sought to tie Harris to Obama.

“Democrats want to evoke memories of 2008,” Republican National Committee Chairman Michael Whatley said in a written statement. “But this isn’t Barack Obama’s Democrat Party — Kamala Harris is even more dangerously liberal.”

Michelle Obama’s change in tone

In a marked shift from her convention speeches eight and four years ago, when she encouraged Democrats to take the moral high road in response to Trump’s attacks, Michelle Obama took a much more confrontational tone Tuesday night toward the Republican nominee.

“Who’s gonna tell him the job he is currently seeking might just be one of those Black jobs?” she said, in reference to a comment Trump had made about immigrants taking “Black jobs.”

Harris would be the second Black president, after Obama.

Earlier, with veiled shots at Trump, the former first lady contrasted him with Harris.

Harris “understands that most of us will never be afforded the grace of failing forward,” she said. “Who will never benefit from the affirmative action of generational wealth. If we bankrupt a business or choke in a crisis, we don’t get a second, third or fourth chance.”

Some Republicans have called Harris, a Black and South Asian woman, a “DEI hire,” an implication that her race and gender were more important than her career and character qualifications. Trump gained an inheritance from his father, who was also a real estate developer.

Trump oversaw bankrupted businesses before he entered politics. And Democrats have said he bungled the response to the COVID-19 pandemic.

Barack Obama also leveled attacks on Trump, calling him “a 78-year-old billionaire who has not stopped whining about his problems since he came down off his golden escalator” when he announced his 2016 presidential bid.

Trump alternative

Both Obamas said Harris provided a strong alternative to Trump.

Not born into privilege like Trump, she has the empathy he lacks, Barack Obama said.

“In other words, Kamala Harris won’t be focused on her problems,” he said. “She’ll be focused on yours.”

Minnesota Gov. Tim Walz, Harris’ running mate, also provided a counterbalance to Trump, Obama said, adding that he loved Walz’s authentic Midwestern persona.

Both Obamas called on Democrats to work hard for Harris’ cause over the 11 weeks until Election Day.

Michelle Obama made “do something” a refrain of her speech.

“You know what we need to do,” the former first lady said. “Michelle Obama is asking you — no I’m telling y’all — to do something. This election is going to be close. In some states, just a handful of votes in every precinct could decide the winner.”

Biden tribute

Barack Obama dedicated the first portion of his roughly half-hour speech to honoring his vice president, President Joe Biden.

Biden guided the country out of the COVID-19 pandemic and led a strong economic recovery while lowering health care costs, Obama said.

And Biden deserved credit for sacrificing his political ambition by bowing out of his reelection race, he said.

“At a time when the other party had turned into a cult of personality, we needed a leader who was steady, and brought people together and was selfless enough to do the rarest thing there is in politics: putting his own ambition aside for the sake of the country,” Obama said. “History will remember Joe Biden as a president who defended democracy at a time of great danger.”

He nodded along as the crowd chanted “Thank you, Joe.”

Appealing to unity

Both Obamas repeated slogans from campaigns that had his name on the ballot and his presidency, seeking to tie his historic election victory to Harris’ campaign.

“On health care, we should all be proud of the progress we made through the Affordable Care Act,” Barack Obama said, referring to the major health care law he championed in his first term. “I noticed, by the way, that since it became popular they don’t call it Obamacare no more.”

Harris “knows we can’t stop there,” he continued, and would work to lower drug costs.

He also called for Americans to focus on common bonds.

“The ties that bind us together are still there,” he said. “We still coach Little League and look out for our elderly neighbors. We still feed the hungry in churches and mosques and synagogues and temples.”

In his keynote address at the 2004 Democratic National Convention, Obama also invoked Little League to stress national unity.

“The vast majority of us do not want to live in a country this bitter and divided,” he said Tuesday. “We want something better. We want to be better.”

The excitement for the Harris campaign showed that was a popular idea, he added.

To close his speech, he invoked the first president nominated at a Chicago convention, elected in the most bitterly divided period of American history — Abraham Lincoln.

“As much as any policy or program, I believe that’s what we yearn for: A return to an America where we work together and look out for each other, a restoration of what Lincoln called, on the eve of civil war, ‘our bonds of affection,’ when America taps what he called ‘the better angels of our nature,’” he said. “That’s what this election is all about.”