By Steve Holland and Trevor Hunnicutt
Democratic presidential candidate Kamala Harris made a surprise appearance at the party's national convention on Monday night, drawing cheers from the crowd as she vowed to defeat Republican rival Donald Trump in the November election.
"Let us fight for the ideals we hold dear and let us always remember, when we fight we win," Harris, the US vice president, said in brief remarks that drew roars from the crowd.
She had been expected to appear later with President Joe Biden, the keynote speaker on Monday, the first night of a four-day event in Chicago.
Biden's appearance at the start of the four-day event caps a dramatic handover to his No. 2 after he was pressured to quit the race last month by party leaders worried the 81-year-old incumbent was too old to win or serve another four years.
Having served as vice president to the first Black US president, Barack Obama, Biden bowed out of the race to allow his own second-in-command to try to make history as the first woman, a Black and Asian American, to hold the nation's highest office.
Hillary Clinton, who became the first woman to secure a major US party's presidential nomination, was due to address the gathering later on Monday.
Clinton fell short two times, losing the party's nomination to Obama in 2008 and the election to Trump in 2016 in a bitter disappointment for the pioneering but polarizing political figure.
During a walkthrough of the convention centre on Monday afternoon, Biden was asked if it was a bittersweet moment.
"It is a memorable moment," he told reporters.
Due to speak at 10.50pm Eastern time (0250 GMT on Tuesday), Biden will portray the Republican former president as a threat to American democracy while touting the achievements of the Biden-Harris administration.
A note of uncertainty
While Democrats gathered for their national convention, thousands of people assembled at a nearby park to protest the party's military support for Israel's Gaza offensive.
The pro-Palestinian protesters were fewer than the tens of thousands that organizers had predicted, but a splinter group left the main march and breached a security perimeter near the convention centre, drawing riot police who detained four people.
The protests injected a note of uncertainty into what is otherwise likely to be a week of celebration, with some on the party's left flank angry over the Biden administration's support for Israel's actions in Gaza.
Hala Hijazi, a business executive from San Francisco, broke down in tears as she spoke to a panel on the war in Gaza attended by 300 people.
"I'm here because I've had over 100 of my family killed in Gaza, two just last week," Hijazi said. "I'm here in their honour. I'm here because they can no longer speak, because that's the least I can do as an American, as a person of faith and as a Democrat."
The protesters appeared unlikely to pressure Democrats to change. The party voted on Monday to approve a 92-page policy platform that does not call for an arms embargo against Israel, a demand of pro-Palestinian groups. The United States approved $20 billion in additional arms sales to Israel on Tuesday.
Harris is riding a historic whirlwind into the convention: her campaign has broken records for fund-raising, packed arenas with supporters, and turned opinion polls in some battleground states in Democrats' favour.
Harris' vice presidential running mate, popular Minnesota Governor Tim Walz, was greeted with chants of "We're not going back" on Monday when he met with groups of delegates.
One prominent backer, however, cautioned fellow Democrats not to be overly optimistic. "Our numbers are much less rosy than what you're seeing in public," said Chauncey McLean, who heads Future Forward, a committee that has raised hundreds of millions of dollars to help elect Harris.
Biden abandoned his reelection bid after his disastrous debate against Trump on 27 June prompted long-time allies, major donors and other party supporters to demand he step aside.
Polls a month ago showed Trump with a clear lead over Biden, but Harris has closed the gap both nationally and in many of the highly competitive states, including Pennsylvania, that will play a decisive role in the election.
"Democrats are fired up," Wisconsin Governor Tony Evers told reporters. "We have a Republican candidate that is sitting there talking gibberish."
Harris will call this week for raising the US corporate tax rate from 21 percent to 28 percent, her campaign said, which would partially undo one of Trump's signature accomplishments during his 2017-2021 White House tenure.
Trump on "Comrade Kamala"
Trump, meanwhile, plans to campaign this week in battleground states that are likely to determine the outcome of the election.
Some major allies and donors have been urging Trump to steer clear of racial and gender-based insults of Harris and focus his attacks instead on her policy record.
At a small business in southern Pennsylvania, he repeatedly referred to Harris as "Comrade Kamala" in an effort to paint her as a communist at an event to discuss economic policies.
- Reuters