Republican senators haven't been willing to openly and aggressively clash with the Pentagon to advocate for a decorated Green Beret fighting for his career after he roughed up an Afghan police chief who was accused of repeatedly raping a boy.

With an Army decision about the soldier's career just weeks away, Sen. John McCain, who chairs the Armed Services Committee, and Sen. Pat Roberts, R-Kansas, told the Washington Examiner they aren't willing to use their full power as senators and block Obama's nominations over the issue.

Instead, they are taking a back-channel approach, building on Rep. Duncan Hunter's more confrontational advocacy on behalf of the Army sergeant.

The Army wants to discharge Sgt. 1st Cass Charles Martland, 33, for an incident in 2011 in which he beat up an Afghan police commander accused of child rape then dragged him to the perimeter gate of the outpost and threw him out.

Martland and another member of his team, Capt. Daniel Quinn, say they only took action after the Afghan police chief laughed after admitting to chaining the 12-year-old boy to a bed and sexually abusing him.

Quinn left the Army, but Martland has been fighting an uphill battle to continue his 11-year career, which has included three combat deployments and several accommodations, including a Bronze Star for his actions during a Taliban ambush.

It's a particularly difficult time for Martland to lose his career: His wife is pregnant with twins, Hunter's spokesman Joe Kasper told the Examiner.

"He is a family man first and foremost and then a soldier," Kasper said. "Are these the types of people we want to be losing [from the military]?"

The Army Human Resources Command has denied Martland's appeals, and recommended he be discharged. Martland has appealed to the Army Board for Correction of Military Records, which has until March 1 to make a final determination or delay its decision.

Rep. Hunter, a former Marine officer and a member of the House Armed Services Committee who has taken up Martland's cause, says the Afghan commander in question has exaggerated his injuries and cites multiple sources for those claims, including a linguist and authorities he says the Army never interviewed.

Hunter has asked McCain, as well as Roberts, to block the nomination of Eric Fanning to be Army secretary until the Army drops the case against Martland. Both McCain and Roberts told the Examiner they're unwilling to place a hold on Fanning's nomination over the Martland case, and have either already addressed the case or are willing to do so in other ways.

A McCain spokesman said the Armed Services Committee has exercised "close and continuing oversight" of Martland's case.

"Senator McCain has full confidence that if Sergeant Martland submits an appeal to the Army Board for Correction of Military Records, he will get the full and fair review of his case that every soldier deserves," the spokesman said.

Roberts is already blocking Fanning's nomination over Obama's efforts to close the prison facility at Guantanamo Bay, Cuba. Hunter last week sent Roberts a letter asking him to consider expanding the hold to fight for Martland's cause.

"The only suitable action, I firmly believe, is to permit Martland to continue his service in the U.S. Army," Hunter wrote.

Roberts, who served as a Marine in his early career, said he is sympathetic to the issue and wants to do something to help, such as sending a "strong letter" to the Army or President Obama. But he said he's not willing to expand his hold on Fanning to stand up for the Green Beret's cause.

"No, I'm not going to do that," Roberts told the Examiner.

"It really gets into an issue that's one of these issues the administration just hasn't touched on or said where we are and what our policy is," he said of the case. "When our service people are confronted with these kind of terrible issues … it's one thing to say 'hands off if it's outside the base.'"

"So it's a pretty big issue," he said. "I'm not on Armed Services or the Intelligence Committee anymore, but I am a Marine."

While McCain won't escalate the fight over Fanning's nomination to include Martland's case, he pressed the Pentagon about it during a high-profile Senate Armed Services Committee hearing on Afghanistan in October.

Referring to Martland's case and the issues surrounding it, McCain called reports about U.S.-trained Afghan police commanders engaging in child rape "disturbing."

"It is precisely because we are fighting for progress and fighting for our values [in Afghanistan] that it has been so disturbing to read reports alleging that some of our coalition partners may be engaged in sexual abuse and other activities that contradict our values," McCain said at the hearing.

He then asked Gen. John Campbell, the top military commander in Afghanistan, to share any actions have been taken to address allegations that the U.S. Army is turning a blind eye to allegations of sexual abuse exemplified in Martland's case.

Campbell said he is working to ensure that every soldier is fully trained about their obligation to report such misconduct instead of taking matters into their own hands. Campbell also told the committee that he has the assurances of Afghan President Ashraf Ghani that his government will not tolerate such criminal behavior and will investigate and prosecute allegations.

Hunter's spokesman said his boss is more than happy to be leading the charge for Martland while McCain and others are taking a less confrontational approach.

"Whether it requires reminding the Army daily, weekly or monthly that there's an expectation that Martland's case be resolved, Rep. Hunter is more than happy to do exactly that — he's entirely fine with carrying that burden," Kasper said in an interview.

The Army would like Congress to see this all has a personnel issue, not a problem with the Army's broader policy of turning a blind eye on child rape in Afghanistan, Kasper said.

"That would prompt Congress to steer clear of any intervention, but we have a direct oversight responsibility on [military] personnel and policy issues and we intend to continue to exercise it," he said.