Moderator Susan Page posed the first question to Harris, revealing the first of nine topics: The coronavirus pandemic.

Noting the president's recent diagnosis, Page asked Harris, "What would a Biden administration do in January and February that a Trump administration wouldn't do?"

True to her form as a prosecutor, Harris -- the first Black woman and first Indian American to take a vice presidential debate stage -- laid out her facts, arguing the administration knew about the threat of the virus in January but didn't act soon enough.

"They were informed that it's lethal in consequence, that it's airborne, that it will affect young people," Harris said. "They knew what was happening and they didn't tell you."

Harris then said the Trump administration still doesn't have a plan.

"Well, Joe Biden does and our plan is about what we need to do around a national strategy for contact tracing, for testing, for administration of the vaccine, and making sure that it will be free for all," she said.

There was no handshake between candidates -- customary at the top of such events -- due to COVID-19 precautions. The audience, limited to under 100 attendees, applauded Pence and Harris as they took the stage.

Former Democratic 2020 presidential candidate Pete Buttigieg, who played Pence at some mock debate rehearsals for Harris, was also spotted in the audience.

Pence and Harris have taken the stage in Salt Lake City for the vice presidential debate. The candidates skipped the traditional handshake due to COVID-19 and are divided by plexiglass.

Harris' chief of staff Karine Jean-Pierre told ABC News Chief Anchor George Stephanopoulos that Harris won't spend the night fact-checking Pence on stage.

Instead, the former prosecutor will "bring the case forward" on how Biden and Harris could lead to a different America.

"This debate is about Donald Trump's failure to contain COVID-19, and not just that but to also help working families," said Jean-Pierre, adding Harris has a "very diverse team" that has prepared her for the debate.

Jean-Pierre also criticized the example Trump has set since testing positive for the novel coronavirus last week.

"You have a president right now when he left the White House, he decided that he was going to make a campaign by removing his mask. His rhetoric has been incredibly dangerous," she said. "As Joe Biden said, it's a tragedy that he believes that he was blessed to have this virus, when people are suffering."

Marc Short, Pence's chief of staff, noted that Harris, like Pence, is "also a very skilled debater and has a record as a prosecutor, so I think it will be a very engaging conversation for the American people and hopefully one that shows a clear contrast in visions between the two campaigns."

Short said Pence will argue the case that the Trump administration protected more American lives in its COVID-19 response.

With less than a month to go until the election, early voting has already begun in 33 states and at least 5.5 million votes have been cast -- hitting record numbers across the nation.

According to the United States Elections Project, spearheaded by the University of Florida's political expert, Michael McDonald, an unprecedented 5,618,155 voters have already voted and at least 69,786,179 ballots have been requested in early voting states.

The coronavirus pandemic plays a factor in explaining the large early voting numbers as well as an increase in voter interest. Voters in 2020 are more eager to cast a ballot ahead of Election Day where polling sites could be viewed as overcrowded during pandemic standards.

Seven states --- California, Colorado, Hawaii, Nevada, Oregon, Utah and Washington -- have an all-mail ballot election meaning anyone registered to vote automatically receives a ballot to their registered address.

-ABC News' Kelsey Walsh

Pence has stood by and pushed the Trump campaign message of "law and order" and has remained a vigorous defender of police. In an interview with ABC News Live Anchor Linsey Davis, Pence said that he and Trump "reject the notion from Joe Biden and others that there's an 'implicit bias' towards minorities in law enforcement."

"The president and I know we don't have to choose between supporting law enforcement and supporting all of the families that live in our major cities," Pence told a crowd of supporters in Lititz, Pennsylvania. "We have done both for the last three and a half years, and we're going to support law enforcement and support our African American and minority families for four more years in the White House."

The vice president has dismissed the "defund the police" movement and has called for more resources and better training and accountability in law enforcement.

On matters of racial discrimination in policing and use of force, Harris has called for the rooting out of racial discrimination. In the aftermath of George Floyd's killing while in police custody she participated in protests in Washington, D.C.

During an appearance on ABC's "The View" in June, Harris was asked by co-host Meghan McCain if she supports the "Defund the Police" slogan, but did not give a direct answer on where she stands.

"We need to re-imagine how we are achieving public safety in America. And to have cities where one-third of their entire budget is going to policing but yet there's a dire need in those same cities for mental health resources, for resources going into public schools, for resources going into job training and job creation. Come on. We have to be honest about this that there isn't a consensus around this because if there were, we would actually see a smarter distribution of resources in our country to address the issues that need to be addressed."

After the shooting by police of Jacob Blake, she met with Blake's family in Wisconsin and spoke with Blake over the phone. She also told NBC News, "I think that there should be a thorough investigation, and based on what I've seen, it seems that the officer should be charged." She's also kept in contact with Tamika Palmer, the mother of Breonna Taylor who was shot by Louisvill, Kentucky, police while she was sleeping in her home.

Harris has called for economic and educational investment in communities of color to create safer, healthier communities. She and Biden have called for an end to no-knock warrants, chokeholds and carotid holds. They want to create a national excessive force standard and create a database to track cops who use excessive force and break the rules. The pair want to end cash bail and private prisons.

"We have to understand that you can't think that the only way to create safe communities is to put more police on the streets, that's not how it's going to work," Harris told pop star Lizzo on an Instagram Live stream in September.

In contrast, Harris wrote in her 2009 book "Smart on Crime," "if we take a show of hands of those who would like to see more police officers on the street, mine would shoot up."

-ABC News' Justin Gomez and Averi Harper