(CNN) Rep. Keith Ellison's past ties to the Nation of Islam and his defense of its anti-Semitic leader, Louis Farrakhan, are resurfacing as he campaigns to lead the Democratic National Committee.

Ellison, the first Muslim elected to Congress, publicly renounced his association with the Nation of Islam in 2006 after it became an issue during his run for Congress, when local Republican bloggers began publishing his old law school columns and photos connecting him to the organization.

"I have long since distanced myself from and rejected the Nation of Islam due to its propagation of bigoted and anti-Semitic ideas and statements, as well as other issues," Ellison wrote at the time.

But several outlets have resurfaced Ellison's past writings as he runs for DNC chair, raising new concerns about his own views and what they would mean for the Democratic Party if he were to be its leader. A CNN KFile review of Ellison's past writings and public statements during the late 1980s through the 1990s reveal his decade-long involvement in the Nation of Islam and his repeated defense of Farrakhan and other radical black leaders against accusations of anti-Semitism in columns and statements to the press. None of the records reviewed found examples of Ellison making any anti-Semitic comments himself.

In one scathing column from 1990 unearthed by CNN's KFile, Ellison accused the university's president of chilling the free expression of black students by openly criticizing a controversial speaker invited to speak on campus by the Africana Student Cultural Center. That speaker, Kwame Ture (also known as Stokely Carmichael), had publicly claimed that Zionists had collaborated with the Nazis in World War II and has been quoted as saying "Zionism must be destroyed."

University of Minnesota President Nils Hasselmo said he "personally found the statements in Ture's speech concerning alleged Zionist collaboration with the Nazis deeply offensive." Ellison, writing under the name "Keith E. Hakim" for the Minnesota Daily, the student newspaper at the University of Minnesota where Ellison attended law school, argued that Hasselmo "denounced Ture's comment without offering any factual refutation of it," and defended Ture's right to speak on campus and to question Zionism.

Ellison wrote, "Concerning Zionism and Ture's speech, the ASCC's position is simply this: Whether one supports or opposes the establishment of Israel in Palestine and Israel's present policies, Zionism, the ideological undergirding of Israel, is a debatable political philosophy. Anyone, including black people, has the right to hear and voice alternative views on the subject — notwithstanding our nominal citizenship."

He added, "Alternatively, the University's position appears to be this: Political Zionism is off-limits no matter what dubious circumstances Israel was founded under; no matter what the Zionists do to the Palestinians; and no matter what wicked regimes Israel allies itself with — like South Africa. This position is untenable."

According to an account by the Anti-Defamation League, Ture said in his speech on UM's campus that "the Zionists joined with the Nazis in murdering Jews, so they would flee to Palestine."

Ellison wrote other columns in law school defending Farrakhan against charges of racism and arguing for reparations for slavery.

A spokesperson for Ellison told CNN that Ellison "rejects all forms of anti-Semitism" and said "the right wing has been pushing these stories for years to drive a wedge between Congressman Ellison and the Jewish community." Since announcing his candidacy for the DNC chair, Jewish groups like the Anti-Defamation League (ADL) and J-Street have come to Ellison's defense on his past associations and writings.

Ellison's involvement with the Nation of Islam would continue after he graduated from law school in 1990. Ellison helped organized the Minnesota delegation to the 1995 Million Man March, which was led by Farrakhan. The Star Tribune reported at the time that Ellison spoke ahead of the controversial Khalid Abdul Muhammad, who was kicked out of the Nation of Islam by Farrakhan two years earlier for making blatantly anti-Semitic comments, at the University of Minnesota in efforts to raise funds for the Million Man March. According to The Star Tribune report, Muhammed's speech at the university was racist, anti-Semitic, and homophobic.

Ellison's spokesperson noted to CNN that "President Obama, Stevie Wonder, Maya Angelou, and many others also attended the March" and said he "had no additional involvement with March organizer Louis Farrakhan or his organizations, has long since denounced him, and rejects all forms of anti-Semitism."

Ellison continued to defend Farrakhan against accusations of anti-Semitism throughout the 1990s.

"Minister Farrakhan is a role model for black youth," wrote Ellison in an Insight News op-ed in 1995. "He is not an anti-Semite."

When the then-executive director of The Minneapolis Initiative Against Racism, Joanne Jackson, came under fire in 1997 for allegedly saying during a forum that Jews are the most racist white people she knows and that she did not think Farrakhan was a racist, Ellison, who identified by his religious name of Keith Ellison-Muhammad, defended her, saying, "She is correct about Minister Farrakhan. He is not a racist. He is also not an anti-Semite." (Ellison would later address this incident in 2006, writing in a letter to a local Jewish group, "While some at that meeting justified her comments, I spoke out in favor of increased dialogue between the Jewish and African-American communities. I believe that Ms. Jackson's alleged remarks were clearly bigoted, discriminatory story, inappropriate, and even ridiculous.")

In 1998, Ellison launched a bid for Minnesota state representative, a race he lost after failing to gain the endorsement of the Democratic Party in the state, known as the DFL. Both the Star-Tribune and Insight News identified Ellison, who at time was still going by Keith Ellison-Muhammed, as deeply involved in the Nation of Islam at the time. During that race, Ellison rebuffed any insinuation he was, himself, anti-Semitic.

"I am opposed to the subjugation of any class or person on account of their religion, national origin, sex, race, or gender," Ellison said. "I reject anti-Jewish attitude from whatever source."

At the time, Ellison hosted a local radio show "Black Power Perspectives." The show, which aired on KMOJ radio, was hosted by Ellison for years under the name "Keith Muhammad."

That same year, Ellison was pictured with copies of The Final Call, the official newspaper of the Nation of Islam. The picture , which was uncovered by the Minnesota Democrat Exposed blog in 2006, was taken at a rally against police brutality.

"The source of this photo is an old right-wing attack blog whose author now regrets his writings," an Ellison spokesman told CNN's KFile. "He readily admits he made 'mountains out of molehills' and speaks favorably about Congressman Ellison's work."

Michael Brodkorb, the blogger who uncovered the photo told CNN: "Ellison will face new scrutiny about his past associations, but he will have the advantage of balancing this discussion with his extensive work in Congress since being elected a decade ago."

WASHINGTON - APRIL 17: U.S. Rep. Keith Ellison (D-MN) speaks to the Consultation on Conscience held by the Religious Action Center of Reform Judaism at the Cannon House Office Building April 17, 2007 on Capitol Hill in Washington. (Photo by Jonathan Ernst/Getty Images)

As recent as 2000, Ellison publicly defended violent, fringe elements of the far-left. He appeared at a fundraiser that year for domestic terrorist Sara Jane Olson, a member of the self-styled revolutionary group the Symbionese Liberation Army (SLA), which is best known for kidnapping heiress Patricia Hearst. Olson was apprehended in 1999 in relation to the 1975 attempted bombings of two police cars and the slaying of Myrna Opsah during a bank robbery.

At the event, Ellison told the Pioneer Press he believed the prosecution of Olson was political. In his speech , Ellison noted he didn't know much about the SLA and he thought Olson was being prosecuted in the court of public opinion because of some of her political beliefs.

"I'm a supporter of anybody who's subject to political prosecution based on their being in a vilified group," he told the Pioneer Press. "Your chances of getting a fair trial are low. I've been waiting for the evidence against her. I don't think they would not cheat to prosecute this woman.''

Ellison also spoke favorably of convicted cop killer Assata Shakur and expressed his opposition to any attempt to extradite her to the United States from Cuba, where she had fled after escaping prison.

"I am praying that Castro does not get to the point where he has to really barter with these guys over here because they're going to get Assata Shakur, they're going to get a whole lot of other people," Ellison said at the event, which also included a silent auction and speech by former Weather Underground leader Bernardine Dohrn. "I hope the Cuban people can stick to it, because the freedom of some good decent people depends on it."

Other prominent black leaders also opposed Shakur's extradition at the time, including Rep. Maxine Waters of California when she chaired the Congressional Black Caucus.

During his successful 2006 run for Congress, Ellison distanced himself from his past support for the Nation of Islam and Farrakhan when the local Republican blogs, Minnesota Democrats Exposed and Powerline Blog, uncovered many of Ellison's past writings.

Ellison publicly renounced the Nation of Islam in a 2006 letter to Jewish groups.

In the letter , Ellison wrote he had seen the Nation of Islam and the Million Man March as positive effort to promote responsibility and economic development in the black community and that he had failed to scrutinize the views of Farrakhan and Khalid Abdul Muhammad and wrongly dismissed concerns they were anti-Semitic.

During the race, Ellison told the Washington Post that his political beliefs had moderated over time. While he said he never said anything homophobic or anti-Semitic, he acknowledged he had been slow to judge those who did.

Ellison's work in the Minnesota legislature, like helping with an ethics complaint against a Minnesota representative who denied that Nazis persecuted gays during the Holocaust, was able to garner him the support of some Jewish groups during his 2006 run for Congress. Those groups stood by him when his past comments on Farrakhan surfaced.

"When several local right wing blogs began attacking him, those in the Jewish community who know and work with Keith rallied behind him," said Rep. Frank Hornstein, a longtime member of Minnesota's House of Representatives. The American Jewish World endorsed Ellison saying they were" convinced that Ellison has had a real change of heart and mind."

Speaking to a synagogue in 2006, Ellison said he was confronting a past he wasn't proud of.

"I wasn't proud of my work with the Nation of Islam," Ellison said , "but I was hoping it wouldn't come up. I have come face to face with my past."

After initial publication of this story, a spokesperson for Ellison pointed CNN's KFile to a post by the congressman on Medium published Wednesday night, where he wrote, "In my effort to pursue justice for the African-American community, I neglected to scrutinize the words of those like Khalid Muhammed and Farrakhan who mixed a message of African American empowerment with scapegoating of other communities. These men organize by sowing hatred and division, including, anti-Semitism, homophobia and a chauvinistic model of manhood. I disavowed them long ago, condemned their views, and apologized."

Minnesota Daily staff contributed research to this report.