Manning has already made two suicide attempts while incarcerated at the maximum-security US Disciplinary Barracks at Fort Leavenworth and went on a hunger strike last year in an attempt to get officials to allow her to undergo gender reassignment surgery.
Speaking to NBC, Manning's aunt, Deborah Manning, said she is more hopeful now than ever before that her niece would be granted clemency.
"I do think it's the last hope for a while,"' she added.
During Manning's trial in 2013, prosecutors argued that the Army private was a traitor, not a 'whistelblower,' who used her military training and skills as a hacker to harm the US and provide assistance to al-Qaeda.
Among the trove of documents Manning had given to WikiLeaks were war logs from Iraq and Afghanistan, diplomatic cables, detainee files from Guantanamo Bay and an infamous video dubbed 'Collateral Murder' that showed an Apache helicopter attack that killed civilians in Baghdad, including children and two news cameramen.
The soldier's defence team sought to paint the defendant as naive and well-meaning, and claimed that the prosecution has failed to produce evidence that Manning's leaks harmed national security or diplomatic interests.
Manning ultimately pleaded guilty and before her sentencing issued an apology to the nation.
"I'm sorry that my actions hurt people," Manning told the court. "I'm sorry that they hurt the United States. I understand that I must pay the price for my decisions and actions."
If Obama decides to commute Manning's sentence, her conviction would stand but she might serve a shorter prison term, or be released.
Manning's supporters have long argued that the 35-year sentence in a maximum security correctional facility was excessive, and that in handing down the harsh punishment, the judge sought to send a message to another high-profile government whistleblower, Edward Snowden.
Manning's aunt said of Chelsea: "I think in a way she was a scapegoat for Edward Snowden."
As news of the possible commutation spread, Snowden himself made an appeal to Obama on Manning's behalf.
"Mr President, if you grant only one act of clemency as you exit the White House, please: free Chelsea Manning. You alone can save her life,' the former NSA contractor said in a tweet.
Snowden, who has been hiding out in Russia after leaking to the press a massive cache of classified material detailing global government surveillance programmes in 2013, has asked Obama for clemency.
If Obama fails to pardon Snowden, his supporters say he may face the death penalty under the incoming administration of Donald Trump, who has called him a "terrible traitor".
Four current and former Army intelligence officers anonymously told NBC News that Manning's disclosures were far less significant than those made by Snowden.
