Just as President-elect Trump is backing down on his campaign promise to have a special prosecutor investigate Hillary Clinton, one major progressive group announced plans Tuesday to launch a probe into the incoming Republican leader.

Center for American Progress Action Fund, founded by Hillary Clinton's former campaign chairman John Podesta, blasted out a fundraising email Tuesday evening asking supporters to donate $100,000 so the group can "mount an aggressive accountability operation" against Trump.

"The Center for American Progress Action Fund is launching a Trump Investigative Fund to hold Trump accountable to every promise, relentlessly track and expose his conflicts of interest, and expose the records and values of the people he is selecting to run the country," ThinkProgress' Editor in Chief Judd Legum wrote. "We'll expand our high-quality investigative team and utilize our vast network of progressive allies to deliver our message."

The group denounced Trump's appointment of former Breitbart News executive chairman Steve Bannon to chief strategist. CAP called for "accountability and vigilance" for "racism," "corruption," and "incompetence."