Biden's campaign announced his three guests to the debate: Kristin Urquiza, Gurneé Green and James Evanoff Jr.

The public first met Urquiza when she shared her story at the Democratic National Convention. She lost her father to COVID-19, and declared his "only pre-existing condition was trusting Donald Trump -- and for that he paid with his life." Urquiza is an environmental advocate at Mighty Earth and co-founded the awareness campaign "Marked by COVID."

Green is a small business owner from Cleveland Heights who was also highlighted during the Democratic National Convention. He owns the Cleveland Heights fashion boutique Chemistry 11. In addition to being a small business owner, Green is a certified health care information technologies analyst and a mother of two.

Evanoff is a service technician in Cleveland. He has eight years of seniority with United Steel Workers and works at ArcelorMittal, which was recently acquired by Cleveland Cliffs.

ABC News' Molly Nagle and Mary Bruce

Trump's first presidential debate with Hillary Clinton in 2016 set the record as the most-watched debate in television history, with 84 million viewers, surpassing the previous record of 80.6 million viewers set between Jimmy Carter and Ronald Reagan in 1980, according to Nielsen.

Trump's second debate with Clinton back in 2016 ranks as the ninth most-watched presidential debate with 66.5 million viewers.

MORE: Trump blames media after DNC tops RNC in TV ratings

On Sunday, a New York Times expose on President Trump’s tax returns revealed decades of tax avoidance and millions of dollars in business losses over the past two decades.

The picture painted by Trump’s returns is sharply at odds with the shrewd, deal-making image the president has tried to fashion as a real estate mogul and TV star on a show built around his business prowess, “The Apprentice.”

Now, five weeks from Election Day, the question is will these new revelations affect the presidential race?

Read the analysis from FiveThirtyEight's Geoffrey Skelley here.

When President Trump rang in 2020, the economy was one of his biggest selling points for reelection. He had inherited a strong economy from the Obama administration, and it continued to grow stronger during his first term. Unemployment was hovering at a 50-year-low, GDP growth was exceeding expectations and Wall Street was riding the longest bull market in its history.

But by spring, all of that came crashing down. While the economy has begun to shakily recoup some of its losses, a full and speedy recovery is anything but assured, making it a top concern for many Americans. According to a poll from the Kaiser Family Foundation released earlier this month, registered voters ranked the economy as the most important issue in deciding their pick for president, putting it ahead of the ongoing pandemic.

Trump is now trying to convince the country that since he oversaw a robust economy before the outbreak, he’s the best candidate to restore it. His opponent, Joe Biden, argues that Trump’s mishandling of the coronavirus compounded its impact on an economy that was inequitable to begin with and that it should be reimagined rather than rebuilt.

Click here to see how the candidates’ economic plans compare.

-ABC News' Shannon K. Crawford

BIDEN'S CLAIM: Biden says 100 million Americans have pre-existing conditions, Trump says he's wrong

FACT CHECK: 100 million or more people have pre-existing conditions in the U.S.

Biden said during the debate that "100 million people" have pre-existing conditions, while Trump said that number was "totally wrong."

"There aren't 100 million people with pre-existing conditions," Trump said. The two candidates were debating about the path forward for health care in America.

Biden, who was arguing that Trump and Republicans would kick people with pre-existing conditions off of health care if they rescinded the Affordable Care Act, is correct that somewhere around 100 million Americans have pre-existing conditions, according to studies.

One study by the Health and Human Services Department in 2017 found that a large percentage of non-elderly Americans have pre-existing health conditions, ranging from 61 million to 133 million.

The study found that "at least 23 percent of Americans (61 million people) using a narrow definition based on eligibility criteria for pre-ACA state high-risk pools, or as many as 51 percent (133 million people) using a broader definition closer to the underwriting criteria used by insurers prior to the ACA" could have been denied health care or offered it at a high price before the Affordable Care Act passed because of pre-existing conditions. The study was published under the Obama administration.

There is a difference, however, between the absolute number of people with pre-existing conditions and the number of people who would be denied coverage under the Affordable Care Act. Experts point out that 54 million non-elderly Americans would've been denied insurance before the ACA, but confirmed that 100 million or more Americans have pre-existing conditions.

"54 million non-elderly adults have a pre-existing condition that would have led to a denial of insurance before the ACA. 100 million or more have a pre-existing condition that would have led to higher premiums or limited benefits," tweeted Larry Levitt, executive vice president for health policy at the Kaiser Family Foundation, referring to a study by the organization.