Kamala Harris v Mike Pence: Why this vice-president debate matters
It's time for the supporting cast to bask in the spotlight. The deputies will have their day in charge. The number-two figures are stepping out of the shadows.
This promises to be a vice-presidential debate like no other.
Some have even called it the most important in history, since it comes as the US president is ill with Covid 19, a virus that's claimed 200,000 Americans and upended 330 million lives. Plus a Supreme Court fight, racial unrest and, and, and...
Wait. Who's in the vice-presidential debate?
In one corner you have Kamala Harris, the woman who aspires to be the first female vice-president in history.
The California senator, 55, is one of the toughest interrogators in Congress, a hardened former lawyer who has left congressional witnesses bloodied after tearing into them in Senate hearings.
In her sights she has an unflappable Republican vice-president who rarely puts a foot wrong under intense media questioning. He won't just be playing defence, either. He'll be looking to exploit his obvious advantage in one area - he's done it before.
Mr Pence is a 61-year-old, softly-spoken, deeply religious man, a Christian from Indiana. Despite their obvious differences, Mike Pence has been a pillar of loyalty to his boss for four years and they've walked in lock-step on nearly every issue and through every controversy.
Isn't it usually a non-event? Who actually cares?
Vice-presidential debates don't usually trouble presidential historians too much, but this year the drama of the election campaign could heighten interest in how the pair fare against each other.
The fact that the president has been seriously ill has reminded the public they have the two oldest presidential candidates in history. Being first in the line of succession has never been more significant, and both debaters will be aware they have to present themselves as ready to step into the world's biggest job.
The first debate between Trump and Biden was also so bereft of serious policy that some have said they're hoping for a proper discussion about the vision for America being offered by each ticket.
It could even also be the final debate of the campaign, depending on whether the president recovers in time.
No wonder the Brookings Institution called it the most important vice-presidential debate ever.
Has Trump's infection forced any changes?
Debate organisers are aware that President Trump could have been contagious during the first debate, and potentially infected Joe Biden and moderator Chris Wallace (though both have tested negative so far), so they want to make no mistakes with this one.
The Commission on Presidential Debates has agreed to seat Kamala Harris and Mike Pence 12ft apart - up from 7ft at the presidential debate.
There will also be a glass shield between each candidate's side of the stage to diminish infections. And no more than 200 people on site at the University of Utah's Kingsbury Hall.
Mr Pence dropped his initial objections to having a Plexiglass barrier on his side of the debate stage.
Will it be as chaotic as the first debate?
Unlikely. Mr Pence and Ms Harris are tough but always civil so the chances of it being as nasty and disruptive as Cleveland are close to zero.
In 2016, Mr Pence was very effective in defending Mr Trump and attacking Hillary Clinton. He was widely credited with coming out of his battle with Democrat VP candidate Tim Kaine with the advantage. It's his trademark to be forceful without ever raising his voice.
Ms Harris debates like the lawyer she once was - she's always controlled. She demolished Mr Biden in a debate when she was running against him for the presidential nomination by focusing laser-like on a vulnerability she identified in his past record on civil rights.
That should make the moderator's job a bit easier.
Definitely. In charge this time is USA Today newspaper Washington bureau chief Susan Page.
Ms Page is a seasoned operator with 10 presidential campaigns under her belt, and she won't be intimidated by the occasion - she's interviewed nine presidents.
So what will they politely debate?
Covid-19, and the Trump administration's handling of it, will clearly be the dominant topic of discussion. Mike Pence is in charge of the presidential task force on the pandemic, and he will be pressed to defend the administration's response.
Kamala Harris will probably be asked about her record on criminal justice as attorney general of California, as well as her shifting positions on healthcare reform. She ran to the left of Joe Biden during the race for the presidential nomination, so Pence's debate success may hinge on how well he is able to pin her more liberal views to Biden.
Finally, four years from now, Pence and Harris could be leading their party's tickets in the general election, so consider this debate a possible sneak preview of political battles to come.
This story originally appeared on BBC.com Check it out here.