WATCH LIVE: Sen. Markwayne Mullin testifies in confirmation hearing for DHS secretary

Sen. Markwayne Mullin, President Donald Trump's pick to lead the Department of Homeland Security, will testify in a confirmation hearing Wednesday before the Senate Homeland Security and Governmental Affairs Committee.

The hearing is scheduled to begin at 9:30 a.m. EDT. Watch live in our video player above.

Trump tapped Mullin to take over the embattled agency from Kristi Noem, who was fired earlier this month after her leadership came under bipartisan scrutiny during tense congressional hearings.

READ MORE: Who is Markwayne Mullin, Trump's new pick for DHS?

Mullin was elected to Congress in 2012 and has branded himself as a businessman and a Washington outsider. As Homeland Security secretary, Mullin would take charge of one of the biggest government agencies, leading the nation's disaster response, counterterrorism efforts, border security and the president's mass deportation agenda. DHS has been largely shut down for more than a month due to a political standstill over immigration enforcement reform, affecting agency operations and leading to long wait times for travelers.

A former mixed martial arts fighter who once challenged the Teamsters president to a fight during a Senate hearing, Mullin has pledged to stay "focused on protecting the homeland" if he is confirmed.

READ MORE: Trump's security pick Mullin poised to inherit a DHS beset by challenges

The Republican Party is considering a pivot on how it approaches immigration enforcement as more voters grow concerned over DHS agents' aggressive tactics, which has led to the shooting deaths of at least three U.S. citizens since Trump retook office.

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