Bernie Sanders attempted to distance himself from Elizabeth Warren Sunday morning by again distinguishing himself as a Democratic socialist.

'Every American has to make his or her own choice about the candidate they want. Elizabeth Warren has been a friend of mine for some 25 years. I think she's a very, very good senator. There are differences between Elizabeth, as you know, said she's a capitalist through her bones. I'm not,' Sanders told ABC News in an interview that aired Sunday morning.

Sanders was referencing a time during an event in 2018 when Warren said, 'I am a capitalist to my bones.'

Even though Sanders and Warren are both progressive candidates in the Democratic primary, the two have vastly different ideologies when it comes to economic structures. Warren identifies as a capitalist while Sanders identifies as a socialist.

Bernie Sanders drew a line between his progressiveness and Elizabeth Warren's. Sanders is a self-proclaimed Democratic socialist. Sanders is reemerging in media appearances following his heart attack earlier this month

Elizabeth Warren, a fellow progressive, has been climbing in the polls and has even earned the No. 1 spot ahead of Joe Biden in some surveys. In a 2018 event, Warren said, 'I am a capitalist to my bones.' And she has repeated the claim since then

Sanders, a 78-year-old independent senator from Vermont, has engaged in a few interviews this week following a heart attack earlier this month.

While in Las Vegas, Nevada on October 1, Sanders suffered a heart attack, which his campaign announced a few days later. The incident raised concerns surrounding the health and stamina of the eldest presidential candidate.

He also used the incident to bring attention to healthcare in the country. In a video released Thursday, Sanders said he couldn't have imagined going through his health issues if he didn't have such good health insurance.

Sanders' campaign proposes a Medicare for All healthcare plan, where every U.S. citizen would have health insurance through the government.

'I think the situation we face in this country of the greed and corruption that is existing in Washington, that is existing at the corporate elite level where you have massive amounts of price fixing going on with the drug companies,' Sanders told ABC.

'I am, I believe the only candidate who's going to say to the ruling class ... enough, enough with your greed and with your corruption,' he continued.

He is suggesting that Warren may have some same perspectives as he does, but feels he could do a better job in giving more opportunities to the 'working class.'

The senator is attempting to distinguish himself from Warren as she continues to climb in the polls.

In recent surveys in some key early caucus and primary states, Warren has even surpassed overall front-runner Joe Biden.

Although Sanders has not provided a timeline for his return to the campaign trial he will still be participating in the fourth round of Democratic primary debates in Columbus, Ohio on Tuesday.

Sanders reassured supporters on Thursday that he will soon return to the campaign trail, claiming he was getting his 'endurance back.'

'I also want to say that I am feeling great. I'm getting my endurance back, and I look forward to getting back on the campaign trail as soon as possible,' a muted Sanders said straight to the camera after thanking people for their support.

In his first emergence from his home in Vermont following the heart attack, Sanders told gathered supporters he was more 'fatigued' than usual in the days leading to the medical incident, and claimed he should have listened to his body.

In a walk back just a day later, Sanders said he 'misspoke,' and will continue a 'vigorous' campaign and rally schedule.

Sanders is also mourning the loss of his daughter-in-law Rainè Riggs, who died Saturday, as Sanders was returning home from Las Vegas, at the age of 46.

Riggs was married to the candidate's son Levi Sanders, and passed just two days after she was diagnosed with neuroendocrine cancer – three weeks after falling ill.