The Senate confirmed Markwayne Mullin as homeland security secretary late Monday, approving President Donald Trump's nominee to take over the embattled department after the firing of Kristi Noem during a public backlash over the administration's immigration enforcement and mass deportation operations.Mullin, a Republican senator from Oklahoma known for his close friendship with Trump, has tried to present himself as a steady hand, saying his goal as secretary would be to get the department off the front page of the news. He takes over at a difficult time as Trump has ordered ICE agents to bolster airport security during a budget standoff in Congress. And he tangled with the Republican chairman of the Homeland Security Committee, who questioned Mullin's character and temperament during last week's combative confirmation hearing.Senators confirmed him on a largely party-line vote, 54-45.Routine funding for the Department of Homeland Security has lapsed since Feb. 14, leading to long waits at U.S. airports as Transportation Security Administration agents call out rather than work without pay. Democrats are demanding the Trump administration make changes in immigration enforcement operations following the deaths of two U.S. citizens during protests this year in Minneapolis. Trump has refused the latest proposal, and talks have stalled.MMA fighter takes on Homeland SecurityWhile the senator comes to the position after more than a dozen years in Congress, and with the management experience of running an expanding family plumbing business in Oklahoma, he has not been seen as a key force in immigration issues.A former mixed martial arts fighter and collegiate wrestler who has led early-morning workout sessions in the members-only House gym, he became close with members of both parties and is often seen as a negotiator in partisan Washington.It is his loyalty to Trump that landed him the job, and he's not expected to sway from the president's approach. Mullin was a strong supporter of Trump's immigration agenda and ICE officers before being tapped for the DHS job."I can have different opinions with everybody in this room, but as secretary of homeland I'll be protecting everybody," Mullin said during his confirmation hearing.Immigration enforcement at center of funding stalemateMullin's first challenge will be to restore routine funding to the department that has been blocked since mid-February as Democrats demand tighter restraints. They want immigration officers to identify themselves and not wear masks; refrain from enforcement operations around schools, churches, hospitals and other sensitive locations; wear body cameras; and obtain a judge's approval on warrants before entering people's homes or private spaces.At his confirmation hearing last week, Mullin sought to portray himself as a steady hand at a pivotal time for the agency — an image that was challenged by the committee chairman, Republican Sen. Rand Paul, in a heated exchange. Democrats are also skeptical, seeing him as a loyal executor of Trump's agenda.Paul voted against Mullin during the committee vote. Democratic Sens. John Fetterman of Pennsylvania and Martin Heinrich of New Mexico joined most other Republicans in advancing the nominee in a Sunday vote."Markwayne Mullin is ready to lead," said Sen. John Barrasso of Wyoming, the No. 2 ranking Republican. He said Mullin will "serve with seriousness and character. He will be a leader who makes our country safer."Mullin comes into office at a time when public support for the president's immigration agenda has fallen after a year of high-profile operations in multiple American cities. Under Noem's leadership, officers were accused of using force to arrest immigrants, detaining them in squalid conditions and bypassing due process to rapidly deport immigrants.Mullin did walk back some of his comments during his confirmation hearing, saying he was wrong to malign protester Alex Pretti after he was shot and killed by an ICE officer. He said that as secretary he would refrain from making judgments before an investigation is carried out.He shed light on other ways he might influence policy when it comes to immigration. For example, he said officers would be required to use a warrant signed by a judge — not the administrative warrants now used by ICE officers — to enter a house except in rare circumstances.He acknowledged the concerns some communities have over building massive ICE detention facilities in their neighborhoods and said cutting off federal funds to so-called sanctuary jurisdictions that don't work with ICE would be a last resort.But ultimately, it is the White House that sets the agenda when it comes to how Trump's vision for immigration enforcement is carried out, and Mullin is expected to follow its lead. Trump faces a strong lobby within the GOP pushing him to make good on his promise to deport 1 million people a year.FEMA and federal disaster aid in fluxMullin will also have his hands full charting a new course at the Federal Emergency Management Agency, which has come under scrutiny as it delivers disaster aid to parts of the country hard-hit by hurricanes and other natural disasters.A growing number of critics, even fellow Republicans, said Noem's policy of personally approving contracts over $100,000 slowed disaster response, and the department still doesn't have a full-time administrator.Mullin presented a fresh approach on federal emergency management during his Senate confirmation hearing, rejecting the idea of eliminating FEMA and saying he would revoke Noem's contract approval rule.__Associated Press writer Lisa Mascaro contributed to this report.