In a post on his social media platform, Trump wrote Hegseth will make a GREAT Secretary of Defense.

"He has my Complete and Total support. Good luck today, Pete!" Trump wrote.

Plus, Trump senior adviser Jason Miller did a morning show blitz praising Hegseth.

"I think Pete Hegseth is going to kill them with kindness," Miller said on CNN, previewing Hegseth's strategy ahead of the hearing.

On Fox News, Miller said he believed Hegseth was the war hero the United States needs and highlighted support from veterans for his nomination.

"I don't see it so much of a challenge. I think it's an opportunity to talk about restoring that warrior ethos, that warrior spirit, back into the military," Miller said as he avoided any concerns of Hegseth's past.

-ABC News Oren Oppenheim and Kelsey Walsh

In his opening statement, obtained by ABC News, Hegseth does not mention the allegations against him but vows to be a "change agent" and bring a "warrior culture" back to the Defense Department.

"I want to thank President Trump for his faith in me, and his selfless leadership of our great Republic," Hegseth will say, according to the prepared remarks. "The troops could have no better Commander-in-Chief than Donald Trump."

"He, like me, wants a Pentagon laser-focused on warfighting, lethality, meritocracy, standards, and readiness," Hegseth will say. "That's it. That is my job."

Hegseth will go on to address his lack of experience compared to previous Pentagon chiefs.

"It is true that I don't have a similar biography to Defense Secretaries of the last 30 years. But, as President Trump also told me, we've repeatedly placed people atop the Pentagon with supposedly 'the right credentials' -- whether they are retired generals, academics, or defense contractor executives -- and where has it gotten us? He believes, and I humbly agree, that it's time to give someone with dust on his boots the helm. A change agent. Someone with no vested interest in certain companies or specific programs or approved narratives," the prepared statement reads.

-ABC News' Rachel Scott

Hegseth, if confirmed, would be in charge of a massive organization of more than 1 million active-duty service members and nearly 1 million civilian workers.

Hegseth has previously discussed going after alleged "wokeness" in the military by firing certain generals, taking aim at DEI initiatives and other programs. He's also said he is generally against women serving in certain combat roles unless they pass high standards men do.

Read more about Hegseth's views on various military issues here.

Hegseth, a former Fox News host who had served in Iraq and Afghanistan as an infantry officer in the U.S. Army Reserve and the National Guard, was nominated by Trump in mid-November.

He quickly faced scrutiny from some lawmakers over his lack of management experience. Then came reports of alleged sexual misconduct and financial mismanagement, which he's denied.

At one point, ABC News reported Trump was looking at possible replacements to Hegseth.

But Hegseth's spent many days on Capitol Hill looking to shore up support, vowing to fight and telling lawmakers he's a "changed man." It appeared he was gaining some Republican support back after his one-on-one meetings with lawmakers, and Trump has since doubled down on his support for his Pentagon pick.

Still, the Senate panel that will question him on Tuesday had quietly sought additional information on some of the allegations before the hearing.