But at 8pm local time (11am AEST), Americans tuned in to what appeared to be a carefully choreographed opening for the four-day unifying confab.
"Every four years we come together to reaffirm our democracy," the convention's moderator, actress Eva Longoria, said in the opening moments.
"This year we've come to save it."
Barack Obama's popular wife Michelle was given the primetime slot on the opening night of the convention, which was to have been held over four days in Milwaukee, Wisconsin, but which is now taking place almost entirely online because of the COVID-19 outbreak.
The former First Lady slammed the performance of President Trump in office, describing the leader as "clearly in over his head."
"Whenever we look to this White House for some leadership, or consolation, or any semblance of steadiness, what we get instead is, and a total and utter lack of empathy."
Ms Obama said Mr Biden was a "terrific vice president" during the eight years he served as her husband's number two.
"I know Joe. He is a profoundly decent man guided by faith," she said.
"He knows what it takes to rescue an economy, beat back a pandemic and lead our country."
"He will tell the truth, and trust science," she said in a jab at Trump, who has been accused of repeatedly ignoring the advice of his scientific advisors on how to respond to the pandemic.
She urged supporters to vote for the Democratic nominee "like our lives depend on it," citing efforts to prevent voters from participating.
"Four years ago, too many people chose to believe that their votes didn't matter...and we've all been living with the consequences."
"This is not the time to withhold our votes and protest or play games with candidates who have no chance of winning. We've got to show up with the same level of passion and hope for Joe Biden."
Vermont Senator Bernie Sanders, who challenged Biden for the nomination from the progressive left, also addressed the convention, which was live-streamed.
"Let us be clear, if Donald Trump is reelected, all the progress we have made will be in jeopardy," Mr Sanders said.
"I say to you to everyone who supported other candidates in the primary and those who may have voted for Donald Trump in the last election, the future of our democracy is at stake...the future of our planet is at stake."
Electing Mr Biden over President Trump is an absolute necessity, he urged his supporters.
"My friends, the price of failure is just too great to imagine."
Mr Kasich, a self-described "lifelong Republican", came out in support of Mr Biden's candidacy.
"Yes, there are areas where Joe and I absolutely disagree. But that’s OK because that’s America."
"We can do better than what we’ve been seeing today, for sure. And I know that Joe Biden, with his experience and his wisdom and his decency, can bring us together to help us find that better way.”
Mr Biden's vice-presidential pick, US Senator Kamala Harris of California, the daughter of immigrant parents from India and Jamaica, will speak on Wednesday.
The night's events, dubbed "We the People", featured a mix of live and pre-recorded speeches.
The speaker list includes several Republicans, including former New Jersey governor Christine Todd Whitman, former Hewlett Packard Enterprise chief executive Meg Whitman and former Republican congresswoman Susan Molinari.
Their inclusion has angered some Democrats who are concerned it will take time away from key progressive speakers such as Mr Sanders and US representative Alexandria Ocasio-Cortez.
But campaign co-chair Cedric Richmond pushed back against that idea, saying: "Remember tonight's theme is 'We the People', not 'We the Democrats".
The coronavirus pandemic forced Democrats to overhaul the convention, largely eliminating the in-person gathering planned for Milwaukee, Wisconsin, and turning it into four nights of prime-time packages of virtual speeches and events.
Mr Biden, 77, who was vice-president under Barack Obama, will be formally nominated on Tuesday to be the Democratic challenger to Trump, 74, in the November 3 election.
His acceptance speech on Thursday will cap the convention.
Democrats hope the opening night line-up will highlight the coalition arrayed against President Trump and offer a contrast with 2016, when lingering bitterness between rivals Sanders and nominee Hillary Clinton contributed to her eventual loss.
This year, Mr Sanders dropped out of the primary race in April and swiftly endorsed Biden.
The first night also features an array of Americans dealing with challenges created by the coronavirus outbreak, including economic fallout, and working to fight racial injustice amid protests against police brutality, organisers said.
Mr Biden leads President Trump in national opinion polls heading into back-to-back convention weeks.
President Trump will be formally nominated for a second term at next week's Republican National Convention, which also has been scaled back due to coronavirus concerns.
Trying to steal the spotlight, the President will make campaign visits to battleground states Wisconsin and Minnesota on Monday and Arizona on Tuesday.
Additional reporting: AFP