The last question of the night was on leadership and what Trump and Biden would say to the people who didn't vote for them on Inauguration Day.

Trump said that we would have to make the country "totally successful," and touted low unemployment numbers among all Americans before the pandemic.

"Success is going to bring us together. We are on the road to success," the president said. "But I'm cutting taxes, and he wants to raise everybody's taxes, and he wants to put new regulations on everything. He will kill it. If he gets in, you will have a depression the likes of which you've never seen. Your 401(k)'s will go to hell, and it'll be a very, very sad day for this country." 

Biden started his answer by saying that as an American president he would represent all Americans. 
"Whether you voted for me or against me, and I'm going to make sure you're represented. I'm going to give you hope," he said.

"We're going to move," Biden added. "We're going to choose science over fiction. We're going to choose hope over fear. We're going to choose to move forward, because we have enormous opportunities -- enormous opportunities to make things better."

TRUMP'S CLAIM: "Through John, who is -- John Ratcliffe, who is fantastic, DNI. He said the one thing that's common to both of them (Russia and Iran), they both want you to lose because there has been nobody tougher to Russia with -- between the sanctions. Nobody tougher than me on Russia."

FACT CHECK: While it is unclear whether Trump's director of national intelligence, John Ratcliffe, told him personally that Russia hopes he would lose the upcoming election, such a statement would contradict what the U.S. intelligence committee has determined.

In August, the Office of the Director of National Intelligence assessed "that Russia is using a range of measures to primarily denigrate former Vice President Biden and what it sees as an anti-Russia 'establishment.'” The office has never stated publicly that Russia hopes Biden will lose the upcoming election.

As for Iran, the office said it determined the country in its interference efforts "seeks to undermine U.S. democratic institutions, Trump, and to divide the country in advance of the 2020 elections."

Ratcliffe in a Wednesday evening news conference revealed both Iran and Russia recently obtained voter registration data in their efforts to interfere in the 2020 election, and that Iran was separately behind "a series of threatening emails that were found to be sent this week to Democratic voters," which he said was "designed to intimidate voters, incite social unrest and damage President Trump."

But Democratic leaders have argued Ratcliffe may have inflated Iran's motivations relating to Trump and instead the country was seeking more broadly to sow chaos in the U.S. democratic process.

U.S. officials have also characterized to ABC News that Russia’s interference efforts both in 2016 and 2020 far exceed that of Iran’s in both scope and complexity.

-ABC News' Alexander Mallin

Climate change -- a hot-button topic for years -- has taken on renewed significance ahead of the 2020 presidential election, with wildfires decimating the West, tropical storms pounding the Gulf Coast and year after year of record temperatures.

Both Trump and Biden largely toe their respective party lines when it comes to issues pertaining to environmental policy.

Throughout his presidency, Trump reversed many American commitments to mitigating climate change, most notably pulling out of the Paris Agreement, removing clean water protections and seeking to fast track environmental reviews of dozens of major energy and infrastructure projects, such as drilling, fuel pipelines and wind farms.

Biden has countered the Trump administration's policies by promising to protect the environment with a proposed a $5 trillion plan.

Here is where each candidate stands on the issues

Trump responded to a question on the impact of his language on racial conflict in the country by touting his work on criminal and prison reform as well as opportunity zones.

"It makes me sad, because I am, I am the least racist person," Trump said. "I can't even see the audience because it's so dark, but I don't care who's in the audience, I'm the least racist person in this room."

Biden responded by saying that the president "pours fuel on every single racist fire, every single one."

When asked about his previous support for crime bills in the 1980s and 1990s, Biden said again that his support was "a mistake."

"I've been trying to change it since then, particularly the portion on cocaine," he said. "That's why I've been arguing that, in fact, we should not send anyone to jail for a pure drug offense. They should be going into treatment across the board."

Trump asked why Biden couldn't change those policies during his time as vice president. 

"Why didn't you get it done? See? It's all talk, no action with these politicians," he said. "Why didn't he get it done? That's what I'm going to do when I become president -- you were vice president along with Obama as your president, your leader, for eight years. Why didn't you get it done?

Biden brought up the Obama administration's work to release 38,000 federal prisoners and grant clemency. After continuing pressing from Trump, Biden said they couldn't get more done because "we had a Republican congress."