Tavis Smiley, host of a public affairs show on PBS, and attorney Vernon Jordan are the latest of a string of high-profile people to file letters of support for Jackson, who is to be sentenced July 3 for stealing $750,000 from his campaign treasury, the Chicago Tribune reported Friday.
Smiley said he didn't condone Jackson's actions, but "they are inconsistent with the character of the public servant that I have worked alongside for the betterment of our democracy through the uplifting of fellow citizens."
The broadcaster said he had known Jackson most of his life.
Jordan, who led former President Bill Clinton's presidential transition team in 1992, said Jackson's efforts to help the less fortunate "should not be forgotten."
Jackson, 48, will be sentenced the same day as his wife, Sandi Jackson, 49. She was convicted of failing to report about $600,000 in joint income between 2006 and 2011.