President Donald Trump commuted the life sentence of Alice Marie Johnson on Wednesday, just days after reality star Kim Kardashian West lobbied the president in an Oval Office meeting to intervene on behalf of Johnson, who was serving a life sentence on drug charges.

Johnson, 63, has been in federal prison more than 21 years after being found guilty in connection to a drug trafficking conspiracy, and she would have died behind bars without the president's clemency. She is one of thousands of Americans serving life sentences for nonviolent offenses, according to a 2013 report by the American Civil Liberties Union, the vast majority of whom are there on drug crimes.

BEST NEWS EVER!!!! https://t.co/JUbpbE1Bk0 — Kim Kardashian West (@KimKardashian) June 6, 2018

"Ms. Johnson has accepted responsibility for her past behavior and has been a model prisoner over the past two decades," the White House said in a statement. "While this administration will always be very tough on crime, it believes that those who have paid their debt to society and worked hard to better themselves while in prison deserve a second chance."

Video from NBC affiliate WVTM of Birmingham showed Johnson throw her arms wide to embrace family after leaving Federal Correctional Institution Aliceville Wednesday.

"I'm free to hug my family," Johnson said. "I'm free to live life. I'm free to start over. I can not — this is the greatest day of my life ... My heart is just bursting with gratitude for what has taken place," She thanked President Trump and Kardashian West.

Kardashian West met with Trump last Wednesday to speak about prison reform and possible clemency for Johnson; she was joined by Shawn Holley, an attorney who assembled a legal team for Johnson that's being paid for by the reality television star.

Johnson's daughter, Tretessa Johnson, said earlier Wednesday in an interview that "I thank her (Kardashian West) from the bottom of my heart. I truly do. I'll never forget what she's done."

"And I thank President Trump also for extending the mercy choice on my mother and giving her a second chance because this is really saving her life. Because she was going to die and die in prison," Tretessa added.

Kardashian West, in several follow up tweets, thanked Trump, his son-in-law, Jared Kushner, who is also a senior White House adviser, and "everyone who has showed compassion & contributed countless hours" to the effort to free Johnson.

So grateful to @realDonaldTrump, Jared Kushner & to everyone who has showed compassion & contributed countless hours to this important moment for Ms. Alice Marie Johnson. Her commutation is inspirational & gives hope to so many others who are also deserving of a second chance. — Kim Kardashian West (@KimKardashian) June 6, 2018

"I hope to continue this important work by working together with organizations who have been fighting this fight for much longer than I have and deserve the recognition," she said in a follow-up tweet.

The American Civil Liberties Union, whose lawyers helped represent Johnson in her bid for clemency, also expressed gratitude to Trump on Wednesday, and pushed him to consider commutations for others serving harsh sentences for nonviolent crimes.

"I urge the president to do the same for other federal prisoners serving extreme sentences that don’t match the offenses, while reforming our draconian sentencing laws that produce these senseless punishments," ACLU attorney Jennifer Turner said in a statement.

A White House official told NBC News earlier that dozens of pardons have been prepared for the president and that he is considering them. There is no indication that Trump will move ahead with any of them.

The official would not disclose the names or offenses of those being considered for clemency. A commutation reduces or eliminates a prison sentence, but does not change the fact of a conviction or restore certain civil liberties, such as the right to vote. A presidential pardon, however, offers complete forgiveness for a federal crime.

Johnson has been a "model prisoner," according to an online petition started by her daughter that said she had mentored women, written and produced plays and become an ordained minister while behind bars. The petition said her part of the conspiracy charge was for passing messages back and forth between traffickers.

"I couldn't find a job fast enough to take care of my family. I felt like a failure. I went to a complete panic and out of desperation, I made one of the worst decisions of my life to make some quick money. I became involved in a drug conspiracy," Johnson told Mic.com in a videotaped jailhouse interview last year that first gained Kardashian West's attention.

"Please wake up America and help end this injustice. It's time to stop over-incarcerating your own citizens. Because that is what’s going on," Johnson added in the same interview.