He speaks at March for Life, the nation's largest annual rally against abortion. She presented a landmark plan to protect abortion rights.

Vice President Mike Pence and Sen. Kamala Harris are set to face off on Wednesday in a debate bound to display their drastically opposing views on the issue, which takes on renewed urgency as the Senate considers the nomination of Amy Coney Barrett for the Supreme Court. Harris is in the unique position of being a sitting Senator who will decide Barrett's fate ahead of the election.

The two vice presidential candidates represent opposite sides of the spectrum on reproductive rights, as nationwide support for abortion rights remains high. A July 2019 ABC News/Washington Post poll found 60% of Americans say abortion should be legal in all or most cases, with only 24% saying abortion access should be harder.

A May 2020 poll by Gallup found similar results, with only 20% of respondents saying abortion should be illegal in all circumstances.

Read more on the candidates' positions on abortion here.

-ABC News' Alexandra Svokos

If Wednesday night showcases Sen. Kamala Harris the prosecutor, consider the new evidence added to her case.

And if Vice President Mike Pence is cast as the best explainer and defender of Trumpism, consider how much harder his job has become.

It's been eight short but incredibly long days since the first presidential debate. Since then, President Donald Trump has struggled to denounce white supremacism; refused to commit to accepting the results of the election; spread falsehoods about the voting process; been diagnosed with COVID-19, amid a full-fledged Washington outbreak; choreographed a triumphant return to the White House to urge the nation not to let the pandemic "dominate"; pulled the plug on further coronavirus relief talks until after the election and then reconsidered the move in some late-night tweets.

Enter the number twos -- in a campaign where there's seldom been more attention on the potential need for their services.

Pre-debate squabbles in Salt Lake City include fighting over plexiglass partitions and more space between the candidates to accommodate social distancing. What's really separating the vice-presidential candidates, though, are campaigns of the men at the top of the ticket -- who have distinct styles that are nothing like those of their running mates or each other.

Four years ago, it was Pence holding steady and calm in a debate with a feisty Sen. Tim Kaine, who faced blowback for his interruptions in a mild-mannered affair. Just last year, Harris' main debate opponent was the man she now shares a ticket with -- bringing set-piece attacks that appeared to nick former Vice President Joe Biden.

Now, amid the chaos of the moment and the relative stability of the campaign, Harris will bring a case that Pence might be uniquely equipped to defend.

-ABC News' Political Director Rick Klein

Sen. Harris underwent PCR testing for COVID-19 yesterday and COVID-19 was not detected, per a Harris aide.

-ABC News' Averi Harper

California Sen. Kamala Harris was selected as former Vice President Joe Biden's running mate on Aug. 11. She is the first woman of color on a major party's ticket, and if elected, she'd be the first woman and first woman of color to serve as vice president.

Her nomination came after serving as senator for California and as the state's attorney general -- and after her own, unsuccessful presidential nomination run. She suspended her presidential bid on Dec. 3, 2019 because, she wrote in an email to supporters, she didn't have the financial resources to continue.

Read more on Harris' background here.

-ABC News' Tessa Weinberg and Sruthi Palaniappan

Page pivoted the conversation to climate change, noting the U.S. has seen record-setting hurricanes in the South and record-setting wildfires in the West this year, setting the stakes and posing the first question to the vice president.

"Do you believe, as the scientific community has concluded, that man-made climate change has made wildfires hotter and more deadly and hurricanes wetter and more damaging?" Page asked.

Pence didn't directly answer but warned Harris would sign the U.S. back into the Paris Climate Accord and falsely claimed Biden and Harris have committed to abolishing fossil fuel and banning fracking.

"President Trump and I believe that the progress that we have made in a cleaner environment has been happening precisely because we have a strong free market economy," Pence said.

Harris, once a proponent of the Green New Deal as both a co-sponsor of Sen. Bernie Sanders' bill and as a presidential candidate -- is now embracing Biden's climate plan and defended her running mate's record.

"First of all, I will repeat, and the American people know, that Joe Biden will not ban fracking. That is a fact. That is a fact," Harris began. "We have seen a pattern with this administration, which is, they don't believe in science."

"Joe sees what's happening on the Gulf states, which are being battered by storms. Joe has seen and talked with the farmers in Iowa whose entire crops have been destroyed because of floods. And so Joe believes, again, in science," Harris said, adding that a Biden-Harris administration would "re-enter the climate agreement with pride."

Page then asked if Pence agrees with Harris that climate change poses an existential threat to humans.

"As I said, Susan, the climate is changing. We'll follow the science," Pence said, before launching into an attack on Biden's tax plan.