(CNN) With just one day left until President-elect Joe Biden takes office, five of his Cabinet nominees faced Senate panels as part of the first step of the confirmation process.
Nominees taking part in confirmation hearings on Tuesday include Janet Yellen, Biden's pick to lead the Treasury Department; Avril Haines, Biden's choice to lead the Office of the Director of National Intelligence; Alejandro Mayorkas, the secretary designate for the Department of Homeland Security; Antony Blinken to lead to State Department; and Retired Gen. Lloyd Austin for Secretary of Defense.
The hearings' late start means that Biden is on track to take office without key Cabinet members confirmed. Still, aides have told CNN it is possible the Senate moves on Wednesday, after Biden is sworn in, to confirm some of the nominees.
Nominees participated in hearings across the halls of Congress on Tuesday. Here are the key takeaways.
Biden's pick for director of national intelligence underscored the need to keep politics out of the US intelligence community -- an apparent attempt to turn the corner after years of tension between Trump and the intelligence community during his time in office.
"To be effective, the DNI must never shy away from speaking truth to power -- even, especially, when doing so may be inconvenient or difficult," Haines said at her confirmation hearing before the Senate Intelligence Committee. "To safeguard the integrity of our intelligence community, the DNI must insist that, when it comes to intelligence, there is simply no place for politics ever."
Notably, Haines, a former top CIA official and deputy national security adviser under President Barack Obama, was introduced by Dan Coats, Trump's first director of national intelligence and a former GOP senator.
Coats, who repeatedly clashed with Trump over Russia's interference in the 2016 election, emphasized Haines' "commitment to bringing non-politicized truth to power and restoring trust and confidence in the intelligence community and the American public."
Blinken also said during his confirmation hearing that the State Department "has to be" a nonpartisan institution, breaking sharply from his predecessor Secretary of State Mike Pompeo, who has repeatedly engaged in political activity while serving as America's chief diplomat.
Yellen, Biden's nominee to head the Treasury Department, told lawmakers that if confirmed, her core focus will be on the needs of America's workers and another coronavirus aid package.
"I will be focused from day one on providing support to America's workers and to small business, putting into effect as quickly and efficiently as I can the relief in the bill that was already passed and then, over time, working for a second package that I think we need to get through these dark times before the vaccination program enables us to go back to life as we knew it," Yellen told the Senate Finance Committee during her confirmation hearing.
Yellen also reaffirmed that Biden eventually "wants to repeal parts of the 2017 tax cuts that benefited the highest income Americans and large companies," as well as "reverse the law's incentives to offshore operations." But she added that Biden has been "very clear" that he does not support a complete repeal of the 2017 tax law.
Biden's nominee to lead the Department of Homeland Security reiterated Biden's commitment to stop further construction of the wall on the southern border of the US.
"President-elect Biden is committed to cease funding for further construction of the border wall. I would execute President-elect Biden's commitment in adherence to the laws that guide us," Mayorkas said during the hearing. He dodged questions about whether he thinks the physical barriers along the southern border be taken down or removed.
That didn't satisfy Sen. John Hawley, for one, who moved to block Mayorkas' quick consideration after the hearing due to his border answer.
Mayorkas also said the dismantling of existing immigration policies created under Trump will take time. He also told lawmakers that he does not recommend defunding Immigration and Customs Enforcement.
"I think President-elect Biden, and people who will be joining his incoming administration have spoken about the fact that there's a commitment to follow our asylum laws to enforce our asylum laws, and that means to provide humanitarian relief for those individuals who qualify for it onto the law," Mayorkas said. "That cannot be accomplished with just the flick of a switch and turned on and day one(.)"
Both Haines and Mayorkas addressed ongoing concerns about domestic terrorism and the spread of conspiracy theories during their hearings -- held in the halls of Congress less than two weeks after pro-Trump rioters stormed the Capitol building.
Haines said she felt "concern and obviously empathy" for those working in the Capitol at the time, calling the images "disturbing." She also said she would work with the FBI and DHS to produce a public assessment of the threat that QAnon poses to the US.
Mayorkas called the threat of domestic extremism "is one of the greatest challenges the Department of Homeland Security confronts, and it has unique capabilities in confronting that challenge."
"If I should have the honor of being confirmed, I will do everything I can to ensure that the tragic loss of life, the assault on law enforcement, the desecration of the building that stands as one of the three pillars of our democracy, and the terror that you felt, your colleagues, staff and everyone present, will not happen again," Mayorkas said.
Later Tuesday afternoon, Retired Gen. Lloyd Austin, Biden's nominee to be Defense Secretary, pledged during his hearing to "fight hard ... to rid our ranks of racists and extremists."
"The job of the Department of Defense is to keep America safe from our enemies," Austin said. "But we can't do that if some of those enemies lie within our own ranks."
Nearly all of the nominees who participated in Tuesday's confirmation hearings previewed the Biden administration's approach to China.
Blinken said at his Senate Foreign Relations Committee confirmation hearing Tuesday afternoon that "there is no doubt" that China "poses the most significant challenge of any nation-state to the United States." He also bluntly said that Trump was right for taking a tougher approach to China, even though he does not agree with the Trump administration's tactics.
Blinken said the US had to "start by approaching China from a position of strength, not weakness." Part of that strength, he said, was in working with allies and engagement with international institutions.
Austin said during his hearing that he saw China as "a pacing challenge" for the Defense Department.
And earlier Tuesday morning, Haines said she supports an "aggressive stance" to deal with China -- one that is "more assertive than where we had been in the Obama-Biden administration."
She called China "a challenge to our security, to our prosperity, to our values across a range of issues" and said the intelligence community's approach to China "has to evolve."
Yellen told lawmakers that if confirmed, she would not relax the US' approach on China, promising to take on "China's abusive, unfair and illegal practices."
"China is undercutting American companies by dumping products, erecting trade barriers, and giving away subsidies to corporations," she said.
Nominees also further detailed how the incoming administration expects to approach Iran.
Haines said that while the incoming Biden administration has indicated it would come back to the table with Iran if Tehran came back into compliance with the Iran nuclear agreement, she noted that "frankly, we're a long ways from that."
Blinken said the incoming administration has "an urgent responsibility to do whatever we can to prevent Iran from acquiring ... (a) weapon or getting close to the capacity to having the fissile material to break out on short notice," but did not offer specific steps with regard to rejoining the Iran nuclear deal.
And Austin said he thinks "Iran's ... behavior continues to be destabilizing."
Blinken and Austin previewed their incoming administration's approach to Israel.
The secretary of state-designate told senators that the incoming administration recognizes Jerusalem as the capital of Israel and said it would leave the US Embassy in the contested holy city.
And both men praised the Trump administration's efforts to normalize relations between Israel and other countries in the Middle East.
Austin further said that he thought the recent agreements between several countries in the region to normalize relations with Israel is "a good thing."
"I think certainly this has put a bit more pressure on Iran and I hope that it will have good effects," he added.
Blinken said that while he applauded the Abraham Accords established during Trump's tenure in office, it presented an opportunity to "create a greater sense of confidence and security in Israel as it considers its relationship with the Palestinians. Because whether we like or not, whether they like or not, it's not just going away."
Austin told senators he supported the incoming administration's priority to overturn Trump's ban on transgender people enlisting in the military. And Blinken said during his hearing that he will swiftly appoint an LGBTQI envoy and will allow embassies to fly the pride flag -- after the Trump administration denied multiple embassies the ability to fly the flag during pride month in 2019.
"This is a matter, I think, of some real urgency," Blinken said of the envoy position, which was left empty under Trump. "We've seen violence directed against LGBTQI people around the world increase. We've seen, I believe, the highest number of murders of transgender people, particularly women of color, that we've seen ever. And so I think the United States playing the role that it should be playing in standing up for and defending the rights of LGBTQI people is something that the department is going to take on and take on immediately."
Blinken also affirmed that he would repudiate the findings of the "Commission on Unalienable Rights" -- Pompeo's keystone initiative, which contended in its report that some rights were not worth defending. Rights groups and advocacy organizations feared it would have damaging effects on human rights abroad and the rights of women and LGBTQ people.
If Biden's Cabinet picks are confirmed, they will make history as the most diverse group to ever lead federal agencies. Four out of five of Biden's nominees participating in confirmation hearings on Tuesday are breaking ground in that regard.
If confirmed, the nominees include the first female director of national intelligence, the first female treasury secretary, the first Hispanic and first immigrant DHS chief and the first Black Pentagon chief.
This story has been updated with additional developments Tuesday.