Some seasoned conservatives wonder if President Donald Trump’s choice of a chief of staff actually matters, and they suggest room for a wild card not on the widely reported short list.

“Trump’s chief of staff doesn’t really matter. He’s going to do what he wants to do,” presidential historian Craig Shirley told The Daily Signal. “Donald Trump should pick somebody he will listen to. We don’t know if there is such a person. He is his own chief of staff.”

Most mentioned contenders for the top White House job under Trump include Rep. Mark Meadows, R-N.C., chairman of the House Freedom Caucus; Office of Management and Budget Director Mick Mulvaney; Treasury Secretary Steven Mnuchin; and U.S. Trade Representative Robert Lighthizer.

The position can matter greatly, said Shirley, author of four books on President Ronald Reagan, who had four chiefs of staff over eight years.

Three—James Baker, Howard Baker, and Ken Duberstein—were “superb,” Shirley said. However, he described Donald Regan’s tenure in the job as “disastrous.”

Trump’s current chief of staff, John Kelly, is leaving the job at the end of the year. The retired Marine general is the second person to hold the post, replacing Reince Priebus, former chairman of the Republican National Committee.

Although Trump’s overall staff turnover is comparably higher than past presidents, the change in chief of staff for the first two years is not unusual, Shirley said.

“People burn out. A chief of staff deals with the president, the first lady, the entire staff, Capitol Hill, and has to be the guy to say no,” Shirley said.

Presidents Barack Obama and Bill Clinton both had chiefs of staff who stayed in the job for less than two years.

Trump should be willing to trust his chief of staff to handle smaller matters while he handles the big picture, Shirley said.

“Reagan was a master delegator and his two best chiefs of staff, Baker and Baker, were also very good delegators,” he said.

Neither Trump’s first nor second chief of staff was a bad choice, said Mark Meckler, president of Citizens for Self-Governance.

“The chief of staff is not a loyalty reward. This requires an exceptional administrator. Kelly was good at imposing structure,” Meckler told The Daily Signal. “Priebus was good at building a bridge to the Republican establishment. I don’t think either were mistakes.”

Here’s a look at what conservatives think of the leading contenders and wild cards for White House chief of staff.

‘Fearless’ Mark Meadows

Meadows has been mostly supportive of the president’s agenda as head of the House Freedom Caucus, a group of conservative members who vote as a bloc.

“Mark Meadows would make an excellent chief of staff,” Jenny Beth Martin, co-founder and national coordinator of Tea Party Patriots, told The Daily Signal, adding:

He understands Capitol Hill. He has demonstrated leadership ability with his chairmanship of the House Freedom Caucus. He understands the threats posed to the Trump agenda by congressional Democrats, and he understands how anti-Trumpers at the FBI, Department of Justice, and other places in the federal bureaucracy are determined to block him from implementing his agenda and keeping his campaign promises. And, as he has demonstrated, he is fearless—exactly the combination of skills and attitude that President Trump needs in that position as we move into the 2020 re-election campaign.

The North Carolina Republican may be the most likely choice to put movement conservatives on board, Shirley said.

“Meadows would delight conservatives. It would be a guarantee that conservatives would always get a sympathetic ear,” he said.

However, Meadows and Trump clashed early in the president’s term over the initial proposal to roll back Obamacare. The House Freedom Caucus and other conservatives said the bill didn’t fulfill Republicans’ promise to repeal the unpopular law.

When the bill initially failed to pass the House, Trump blamed the Freedom Caucus, among others.

‘Obvious Choice’: Mick Mulvaney

Mulvaney, the OMB director, has for the past year also been acting director of the Consumer Finance Protection Bureau at the same time.

He knows how to run large organizations, Meckler said.

“The only relatively obvious choices to me is Mick Mulvaney,” Meckler said. “He has done a good job running both the OMB and, briefly, the CFPB. He has proven himself as an able administrator. The only downside is that the president would have to find a new OMB director.”

That’s the problem for Martin, who said she wants Mulvaney to remain as budget director.

“Mick Mulvaney has done yeoman’s work, wearing two hats as director of OMB and as acting director of the Consumer Financial Protection Bureau,” Martin said. “We need him in place at OMB as we go into a critical budget cycle.”

Mulvaney reportedly isn’t interested in the job of chief of staff, but would be interested in becoming secretary of either the Commerce or Treasury departments. That would require another Cabinet vacancy.

Trump Family Choice? Steven Mnuchin

Mnuchin, the treasury secretary and former Goldman Sachs executive, helped push through the Tax Cuts and Jobs Act in late 2017.

Mnuchin reportedly wants to remain in his current job, but CNBC reported Trump family members are urging the president to tap him for the post of chief of staff.

Shirley, however, said Mnuchin might not be effective in this role.

“He comes out of Wall Street,” Shirley said. “The chief of staff has got to be political, conservative, know the ways of Washington, and [be] great with the national media.”

While in the private sector, Mnuchin donated to both Democratic and Republican candidates, so it’s not likely he would be as welcomed by the conservative movement as either Meadows or Mulvaney.

Martin said she had no objections to Mnuchin on other grounds, aside from saying he should remain at the Treasury Department.

“Steven Mnuchin has been a good Treasury secretary,” Martin said. “He helped shepherd through Congress last year’s historic tax reform. But it’s my understanding he would prefer to remain in place at Treasury, and I think President Trump would be wise to keep him there.”

Trading Jobs? Robert Lighthizer

Lighthizer, the nation’s trade representative, has promoted the president’s “America first” agenda, including tariffs.

This itself might not go over well with conservatives—many of whom strongly favor free trade, Shirley said.

Lighthizer was a key figure in forging the new trade agreement among the U.S., Mexico, and Canada—which is largely an updated version of the North American Free Trade Agreement.

Lighthizer also is still in the middle of handling multiple other trade negotiations, chiefly with China.

“Robert Lighthizer is taking the lead on critical trade negotiations with China,” Martin said. “Now is not the time to shuffle the players in the middle of that negotiation.”

Then there are the wild cards.

From Justice to the White House? Matt Whitaker

Matt Whitaker has been the acting U.S. attorney general since early November.

Before that, he was the chief of staff for Attorney General Jeff Sessions, who Trump ousted after the Nov. 6 midterm election.

During the George W. Bush administration, Whitaker was a U.S. attorney in Iowa.

Before joining the Trump administration, he was executive director of the Foundation for Accountability and Civic Trust, a government watchdog group.

Trump reportedly is considering Whitaker for the post, and his administrative experience is one reason.

Still, Meckler said, he isn’t sure Whitaker’s administrative experience relates to the political experience also necessary for a successful White House chief of staff.

“Matt Whitaker has been mentioned, but, his experience [in the Justice Department] is not related to what a chief of staff would do,” Meckler said. “A chief of staff works with every branch of government.”

Loyalty Matters: David Bossie

David Bossie, president of the conservative group Citizens United, has co-authored two books on Trump with former Trump campaign operative Corey Lewandowski.

Now, Bossie reportedly is a possibility for the job of chief of staff.

Bossie was also among the first to advise Trump on running for president as far back as 2011, when Trump considered jumping into the 2012 election.

“Trump puts a big premium on loyalty, and Bossie has been very loyal,” Shirley said.

Though likely a long shot, Bossie would be a good fit for the job, he said.

“He knows how Trump thinks, he’s had experience with campaigns and practical experience,” Shirley said. “He’s also good on TV and could be what Trump needs.”

‘Back in the Fray’ for Newt Gingrich?

Former House Speaker Newt Gingrich has been an adviser to Trump, a campaign booster, and a defender on cable news shows.

Gingrich also wrote two books on Trump in the past two years.

Generally known as an ideas man, Gingrich did run the House of Representatives as speaker from 1995 to 1999.

“If Trump asked Newt, my guess is that he would say yes,” Shirley said.

However, it’s something he would have to consider.

“He would have to ask himself if he wants to jump back into the fray,” Shirley said.

Gingrich is “respected by Reaganites, Trump supporters, and even moderate Republicans,” Shirley said. “He would risk undoing all of that.

“But he loves the sting of battle and might relish another chance to engage.”