Chicago (AFP) - Barack Obama will use the Democratic National Convention in Chicago to anoint Kamala Harris the party’s future on Tuesday and, as the first Black and South Asian woman presidential nominee, heir to his trailblazing legacy.

His wife, former US first lady Michelle Obama, told adoring convention goers “something magically wonderful is in the air.”

“It’s the contagious power of hope,” she said, calling Harris “my girl” and saying that hope – the rallying cry of her husband’s successful 2008 campaign – “is making a comeback.”

His turn will amp up the already buoyant mood in Chicago where President Joe Biden delivered his own emotional speech late Monday less than a month after ending his reelection bid.

“In 2012 I got to vote for him, and everyone was pushing Michelle Obama to run for president, but now we have Kamala. So I just think that this is, in a sense, them passing on the torch,” said attendee Tomara Hall, 35, from California.

Harris’s husband, Second Gentleman Doug Emhoff, said “she is ready.”

“She brings both joy and toughness to this task,” he said to cheers, recounting personal stories like paying for college by working full time at McDonald’s, as well as referring to his divorce.

“At this moment in our nation’s history, she is exactly the right president.”

With the party united and Harris polling strongly, Democrats are making clear they believe they can defeat Donald Trump.

The Republican nominee had seemed set to regain power in November’s election until Biden upended the race by dropping out and endorsing his vice president.

Comparisons are already being made by Democratic faithful to Obama’s historic 2008 campaign, where a tidal wave of enthusiasm carried him to the White House.

Bullish delegates symbolically nominated Harris as their candidate in a boisterous roll call, following a paper exercise to confirm her as their standard bearer earlier this month.

“Thank you… see you in two days, Chicago,” she said to delegates via video link from her event in Milwaukee to huge cheers.

Harris, who was received rapturously in Chicago at her debut appearance before Biden spoke, was in Milwaukee Tuesday for an event at the basketball arena where Trump attended the Republican convention just a month ago.

The choice of the 18,000-seat arena will rile Trump, who has been rattled that 59-year-old Harris, unlike Biden, is able to draw the kinds of crowds the Republican has long attracted to his events.

Addressing both crowds simultaneously highlighted that she had filled the DNC and RNC venues.

- ‘Hardest glass ceiling’ -

Trying to pry media attention away from the Democratic convention, Trump is holding events all week and on Tuesday spoke about what he says is Harris’s “anti-police” stance.

At an event in Howell, Michigan, he attacked what he called “the Kamala crime wave.”

“You can’t walk across the street to get a loaf of bread – you get shot,” he said flanked by police officers and their cars, falsely claiming there has been a 43 percent increase in violent crime.

While allies have pleaded publicly for Trump to focus on policies and stop his barrage of personal insults against Harris, he has not stopped.

On Monday the DNC floor belonged to Biden, who delivered a swan song after being forced to abandon his reelection bid amid deep concerns that at 81 he is too old and frail to defeat Trump.

Biden has recast what might have been a humiliating moment into a narrative of sacrifice, passing on the torch to his younger protege.

“It’s been the honor of my lifetime to serve as your president. I love the job, but I love my country more,” he said, wiping away a tear amid thunderous applause before embracing Harris on stage.

The other star speaker Monday was Hillary Clinton, who in 2016 was the first female presidential nominee of a major party, but lost to Trump in an election that opened up one of the most turbulent eras in recent US politics.

Harris, Clinton said, will be the one to break “the highest, hardest glass ceiling” in the country.

Twenty million people watched the first night of the DNC, ratings monitor Nielsen said, beating viewers for the inaugural evening of the Republican gathering that drew 18.1 million.

Local media reported that Chicago hotels housing convention attendees had received bomb threats, but city authorities did not comment.