President Trump’s search to replace departing Interior Secretary Ryan Zinke did not conclude last week as it was expected to and could stretch into the new year.

A few new contenders have emerged as some of the earlier prospects have faded, according to sources close to the Trump administration.

Colorado native David Bernhardt, the Interior Department deputy set to become acting secretary next month, is still viewed as Trump’s safest bet to run the agency on a permanent basis, according to allies of his and sources close to the White House.

But Bernhardt has competition for the job, and Trump won’t make a decision this week, as the president is preoccupied with the government shutdown fight, the resignation of Defense Secretary Jim Mattis, and the fallout from his decision to remove U.S. troops from Syria.

Bernhardt, who is expected to be named acting Interior secretary as soon as Zinke leaves on Jan. 2, could be the easiest transition for the Trump administration, according to his allies.

“He has more experience in that building working on these issues than any predecessor,” Jon Hrobsky, an attorney who worked with Bernhardt in President George W. Bush’s Interior Department, told the Washington Examiner. “The uniqueness of David for this job is there has never been anyone more qualified to do it.”

But he would have to overcome criticism of his past ties to energy lobbyists.

Bernhardt worked with Hrobsky at the law firm Brownstein Hyatt Farber Schreck, where the former represented oil and gas companies and water districts. His past business history has provided ammunition to critics who say he is too conflicted to lead the Interior Department, which oversees the country’s 500 million acres of public land, including 59 national parks.

His former client list ranges from offshore oil and gas drillers like Eni Petroleum, onshore drillers like Noble Energy and Halliburton, and industry trade associations, including the Independent Petroleum Association of America and the National Ocean Industries Association.

Meanwhile, at least two more candidates, Cynthia Lummis, a former congresswoman from Wyoming, and Rep. Steve Pearce, R-N.M. are expected to receive interviews for the job, sources said.

Pearce is leaving Congress after failing in a bid for governor of New Mexico, where he lost in November to Democrat Michelle Lujan Grisham.

“Congressman Pearce is actively pursuing the role and has been included in conversations the president has had about the position,” a congressional staffer familiar with the process told the Washington Examiner. “If nominated, he would be honored to accept and serve as secretary DOI.”

Others like Rep. Jeff Denham, R-Calif. and Sen. Dean Heller, R-Nev., both of whom recently lost re-election, are interested in the job, but it’s unclear whether they are serious contenders.

Still, Denham is openly campaigning for it, recently telling the Los Angeles Times, “I am on the president’s list.”

Jessica McFaul, a spokeswoman for Denham, told the Washington Examiner her boss has had “conversations with the White House” about the position. She highlighted Denham’s experience working on water and land issues and wildfire prevention.

A few other previously mentioned candidates, including Rep. Raul Labrador, R-Idaho – who opted to not seek re-election and ran unsuccessfully to be his state’s governor – and Rep. Rob Bishop, R-Utah, are not likely to be nominated, sources said.

The lack of a definitive favorite among lawmakers and former congressmen could move Trump back to Bernhardt, who already knows the agency.

In his Interior role, observers say Bernhardt has been leading the day-to-day policymaking process at the agency, specifically focusing on easing permitting processes and environmental reviews to open more federal land to oil and gas drilling, and reforming endangered species protections to make the law less cumbersome and restrictive to developers.

“The department is in very capable hands with David Bernhardt , who would make an excellent secretary himself,” Kathleen Sgamma, president of the Western Energy Alliance, told the Washington Examiner. “However long it takes for President Trump to nominate and the Senate to confirm, Bernhardt will continue to implement the energy dominance agenda that is already well in motion and which he has had a guiding hand in.”

Bernhardt, 49, is a former high school drop-out from rural Colorado who earned his law degree from George Washington University before working at Interior from 2001 to 2009, and eventually rising to the No. 3 position at the department as its solicitor general. He would have to be confirmed again if nominated as Interior secretary.

Other industry leaders, and Trump allies, prefer a nominee with more political experience, and say Bernhardt is more effective in a less visible policy role.

“He’s more effective where he is,” Dan Eberhart, CEO of the oil services firm Canary and a Trump donor, told the Washington Examiner. “If he’s promoted to the political role, someone else will have to actually run the agency on a daily basis. It that the best move for Trump’s agenda? Appointing a political could solve that problem.”