VP debates are the often-forgotten sideshows to the main event, but with President Donald Trump recently hospitalized with Covid-19 and Joe Biden hoping to be elected as the oldest president in American history, this one is expected to draw record audiences.
"Americans will be anxious to hear from these running mates, who could possibly be required to assume the presidency themselves," said Mitchell McKinney, the director of the Political Communication Institute at the University of Missouri, who has consulted with the Commission on Presidential Debates, the nonpartisan group that runs the events.
Harris is the first woman of color on a major party ticket in American history and Biden has highlighted the chance to make history by releasing a new campaign ad showing a young black girl watching in awe as Harris accepts the vice presidential nomination.
Pence has proven to be a loyal, if quiet, junior partner to Trump and an able debater. Polls showed viewers thought Pence bested Tim Kaine, Hillary Clinton’s running mate, in their 2016 faceoff, though that debate attracted the lowest rating in almost two decades.
Wednesday' debate, which kicks off at 9 p.m. ET in Salt Lake City, Utah, will like prove more memorable. Here are five things to watch:
1. How hard does Harris hit Trump?
The California senator is a former prosecutor who has made headlines for her cross-examinations of Trump appointees in hearings and spoke often during her presidential run last year about how she would relish the chance to "prosecute the case" against the president on a debate stage with him.
She’ll have the next best thing by sharing the spotlight with Trump's No. 2 but may feel compelled to pull a punch or two as Trump continues his battle with the coronavirus.
Biden, who has made civility a central theme of his campaign, pulled his TV attack ads after the president tested positive and said Monday at an NBC News town hall that he regrets calling Trump a "clown" in their own debate last week.
Working in Harris’ favor, though, is the fact that polls suggest the American public seems to have little sympathy for the president and believe he was reckless with his handling of the virus, an attitude likely to be compounded by Trump's decision to remove his facemask on the balcony when returning to the White House Monday night, even though he may likely still be contagious.
2. The Covid-19 pandemic
Trump and fellow Republicans have tried to shift focus away from the pandemic to the economy and questions about Biden's policies and fitness for office in the runup to the election, but the ongoing outbreak at the White House makes that even more difficult than ever.
Pence, in particular, will have no choice but to answer for the administration's response to the pandemic since he is the one in charge of it as chairman of the White House Coronavirus Task Force.
The vice president has been more deferential to the experts and less brash in flaunting guidelines than Trump, but he'll have to thread a needle between the medical experts and a boss who is sure to be watching and unlikely to tolerate any daylight between himself and his VP on mask-wearing or his own safety precautions.
The stage and debate hall will make the issue unavoidable.
3. Understudy auditions
People vote for the top of the ticket, not the running mate and they know it. "My primary role is to be Hillary Clinton's right-hand person and strong supporter," Kaine said in the opening remarks of his debate with Pence.
Trump's name appeared 144 times in the transcript of that 2016 faceoff and Clinton's name 102 times, while Pence's name was heard only 55 times and Kaine's just 41.
In 2004, moderator Gwen Ifill felt compelled to ask the vice presidential candidates to answer a single question without mentioning their presidential running mate, but Democrat John Edwards couldn't make it two sentences before uttering "John Kerry." "I'm sorry. I broke the rule," he said.
But this time may be different since Biden would break the record set by Trump of being the oldest president in American history to serve as president and both VP candidates must be thinking, at least in the back of their minds, about the 2024 or 2028 elections, if not sooner.
"Both are vested in being seen as the future thought leaders of their respective political parties," said debate expert Ed Lee of Emory University. "With two septuagenarians at the top of the tickets, Pence and Harris enter the debates considering their political lives after the 2020 campaign. Neither is interested in reproducing the Trump-Biden anti-debate."
4. Contrasts in style and more
Harris and Pence are as different from each other as they from the top of their tickets.
Harris is the daughter of black and Indian immigrants who favors sneakers with blazers, casts herself as a progressive and won her first statewide election after Biden had already qualified for Medicare.
Pence is an evangelical former talk radio host who was worrying that Disney was surreptitiously promoting feminist anti-family values the same year Trump was divorcing his second wife amidst tabloid rumors about affairs with other women.
The vice president's persona is sober and aw-shucks Midwestern. Harris' is of a swaggering cosmopolitan.
The result could, potentially, be a far more substantive debate than the Trump-Biden train wreck, with the message being delivered by cooler messengers.
"She will be meticulously prepared to thoroughly dissect their governing record, especially on coronavirus," said Ian Sams, the former press secretary on Harris' presidential primary run. "Unlike the last debate, there won't be a gorilla in the room throwing feces, so I don't expect it to devolve into a petty personal insult fest between them, especially because Pence is a good debater with a homespun style."
5. Return of the Proud Boys?
It may seem like an eon ago, but the big news last week was the president telling a violent right-wing group tied to white supremacy to "stand back and stand by" when asked if he would denounce white supremacists.
Pence has been far more willing to condemn such groups when Trump has equivocated, including after the 2017 unrest in Charlottesville, Virginia.
"We have no tolerance for hate and violence from white supremacists, neo-Nazis or the KKK," Pence said at a press conference. "These dangerous fringe groups have no place in American public life and in the American debate, and we condemn them in the strongest possible terms."
When pressed about Trump's reluctance to be so clear, Pence has deflected by blaming the media for making too much of Trump's comments. But on a debate stage, he may not be able to deflect as easily.
This article originally appeared on NBCNews.com.