Both vice presidential nominees are seasoned debaters. During her ill-fated presidential primary bid, Harris participated in several debates and made headlines for her zingers, including a clash with Biden over busing to integrate schools. Expectations are high for her in the matchup against Pence, who hasn’t participated in a debate since 2016 but has held his own ground in the past.

In an interview with Hillary Clinton for her podcast “You and me Both,” Harris spoke about the challenges of preparing the debate, including her expectation that Pence could offer “a series of untruths” from the debate stage.

“I don't necessarily want to be the fact checker,” Harris said in the interview. “At the same time, you know, depending on how far he goes with whatever he does, he’s going to have to be accountable for what he says.”

Pence has called Harris a “skilled debater” and has told supporters at campaign events that he looks forward to being on stage with her, though he has remained mostly tight lipped about his expectations or how he’s been preparing for the matchup.

In 2016, Pence participated in the vice presidential debate against Sen. Tim Kaine and was seen to have successfully thwarted attacks over comments Trump made about women and Mexican immigrants, as well as his policy proposals.

During his debate against Kaine, Pence was disciplined, poised and polished and largely waited for his turn to get a response in.

-ABC News' Justin Gomez and Averi Harper

Two, five-foot tall plexiglass walls will stand between Vice President Mike Pence and Sen. Kamala Harris at Wednesday night’s debate.

The thick plastic barriers, approved by the Commission on Presidential Debates, will try to prevent the possible transmission of the coronavirus as Pence and Harris face off onstage for 90 minutes.

The Debate Commission said the plexiglass was part of a “variety of health safety protocols,” according to a factsheet. “Plexiglass will be used as part of the CPD’s overall approach to health and safety.”

Experts say that among the many protective measures put in place, the proposed plexiglass may not be the most effective option, particularly in light of updates from the Centers for Disease Control and Prevention to its guidelines on Monday acknowledging the potential for airborne transmission of the virus while indoors.

According to the CDC, it's possible for the virus to be transmitted beyond 6 feet by forming particles that can linger in the air for prolonged periods of time when infectious individuals “cough, sneeze, sing, talk, or breathe." The risk of airborne transmission is greatest in poorly ventilated indoor spaces as well as during prolonged exposure. Pence and Harris will be 12 feet apart from each other and from the moderator.

The clear dividers on stage could offer an added layer of protection, but it should not be a standalone measure, experts say.

More on experts concerns about safety protocols for the debate can be found here.

-ABC News' Sasha Pezenik and Ramie Fathy

Amid the controversy surrounding a plexiglass barrier at the vice presidential debate Wednesday, a number of Senate debates across the country have utilized the measures.

In last Friday's South Carolina debate, Democratic challenger Jaime Harrison brought his own plexiglass divider to his debate against Sen. Lindsey Graham.

Both candidates said they tested negative the day before the debate and those attending had to fill out a questionnaire saying they had no symptoms.

The Arizona Senate debate on Tuesday night also saw the candidates using plexiglass dividers.

In Colorado, Sen. Cory Gardner and Democratic challenger John Hickenlooper were separated with plexiglass dividers. Both candidates tested negative prior to the debate.

In North Carolina's debate last Thursday, plexiglass wasn't used, but Sen. Thom Tillis and challenger Cal Cunningham were socially distanced from each other and the moderator.

In Iowa, Theresa Greenfield and Sen. Joni Ernst shared a table with the moderators. All were separated by plexiglass barriers.

-ABC News' Meg Cunningham and Kendall Karson

Women's rights and advocacy organizations on the left have been working together to promote Harris's candidacy. This week they are gearing up too against what they fear will be sexist or otherwise biased attacks during the vice presidential debate Wednesday.

The long list of organizations, including BlackPAC, Color of Change PAC, EMILY's List WOMEN VOTE!, Planned Parenthood Votes! and UltraViolet say they are working in tandem on messaging and outreach. On the phone with ABC News, Shaunna Thomas, the head of UltraViolet, argued that female politicians are still more likely to face attacks -- subtle as they may be -- about their qualifications, trustworthiness and character. She said the coalition was planning to release content on social media and around neighborhoods Wednesday with an eye toward women of color in battleground states.

They want to underscore again the historic nature of the ticket.

"A lot of people are excited about this long overdue and historic moment for women of color and the whole country. Never has a woman of color served in such a position ... and it's time," she said.

The coordinated push comes as Biden again leaned into the issue of race and inequity in America on Tuesday during his event in Gettysburg, Pennsylvania.

"I think about what it takes for a Black person to love America that has a deep love for this country that has -- for far too long -- never been recognized," he said on the historic Civil War battlefield after talking about his conversations with the families of Black Americans whose loved ones have been killed by police.

-ABC News' MaryAlice Parks

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