U.S. Rep. Jesse Jackson Jr. (D-Ill.) announced his resignation from Congress Wednesday.

Jackson formally submitted his letter of resignation Wednesday afternoon, a congressional aide reportedly told BuzzFeed's D.C. Bureau Chief John Stanton.

(Scroll down to read Jackson's resignation letter, embedded below.)

The Chicago Democrat's brother Jonathan Jackson told the Chicago Tribune earlier Wednesday that the congressman will announce he is leaving Congress in a letter to House Speaker John Boehner early Wednesday afternoon. A Boehner aide confirmed to The Hill's Daniel Strauss that they have received Jackson's resignation letter, a report the Associated Press confirmed.

JJJ Resignation

In the letter, Jackson acknowledges -- for the first time -- the federal investigation into his campaign contribution spending, but cites his health as the reason for his resignation.

"I am aware of the ongoing federal investgation into my activities, and I am doing my best to address the situation responsibly, cooperate with the investgators, and accept responsibility for my mistakes, for they are my mistakes and mine alone," Jackson wrote in the letter.

CNN previously reported that Jackson will announce his resignation from the House floor, but Jackson's condition will preclude him from speaking Wednesday, according to the Sun-Times.

Jackson, 47, reportedly had planned to discuss his political future with his staffers in a conference call Wednesday, but that call was canceled abruptly upon news of the call going public Tuesday evening. The congressman is reportedly engaged in ongoing plea negotiations with the feds concerning allegations that Jackson used campaign contributions for personal use.

That reported probe is unrelated to an ongoing "pay-to-play" ethics investigation concerning whether Jackson was aware of efforts to raise money for imprisoned former Gov. Rod Blagojevich in exchange for his appointment to the Senate in 2008.

The congressman has been away from work since June as he sought treatment for bipolar disorder at the Mayo Clinic, which readmitted him last month. His whereabouts have remained unknown in recent days and the congressman had remained silent on the heels of his leaving the Minnesota clinic, for a second time, early last week.

Jackson was handily reelected to his ninth term in Illinois' 2nd congressional district earlier this month despite only addressing his constituents through one robo-call during the campaign season.

From the Associated Press:

Illinois Gov. Pat Quinn, a Democrat, now has five days to schedule an election to replace Jackson, and the election must be held within 115 days, according to election officials.

The vacancy left by Jackson's departure creates a rare opportunity for someone else to represent his district, which is made up of South Side Chicago neighborhoods, several southern suburbs and some rural areas. Even this year, when Jackson was absent during the crucial final months of campaigning, he easily defeated two challengers on the ballot, Republican college professor Brian Woodworth and Independent postal worker Marcus Lewis.

Cook County Clerk David Orr said Wednesday in a press conference that the special election could be held on either Feb. 26 or April 9, ABC Chicago reports.

Jackson, son of civil rights leader Rev. Jesse Jackson, was first elected to Congress in a special election in 1995. His wife, Sandi Jackson, is a Chicago alderman representing the city's 7th ward.

Related on HuffPost:


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  • Jesse Jackson Jr.

    FILE - In this March 21, 2010 file photo, Rep. Jesse Jackson, Jr., D-Ill., uses his PDA to photograph demonstrators outside on the U.S. Capitol as the House prepares to vote on health care reform in Washington. When Jackson disappeared on a mysterious medical leave in June 2012, it took weeks for anyone in Washington to notice. Jackson has never lived up to the high expectations on the national stage.

  • Jesse Jackson, Jr.

    FILE - In this Jan. 5, 2011 file photo, Rep. Jesse Jackson, Jr., D-Ill., is pictured before a ceremonial swearing in of the Congressional Black Caucus on Capitol Hill in Washington.

  • Jesse Jackson Jr.

    FILE - In this May 16, 2011 file photo, U.S. Rep. Jesse Jackson Jr. attends ceremonies for Chicago Mayor-elect Rahm Emanuel in Chicago. (AP Photo/Charles Rex Arbogast, File)

  • Jesse Jackson Jr.

    FILE - In this Tuesday, March 20, 2012 file photo, U.S. Rep. Jesse Jackson Jr., D-Ill., thanks supporters at his election night party in Chicago. Jackson's office announced Monday, June 25, 2012 in a news release that the congressman has been on a medical leave of absence since June 10 and is being treated for exhaustion. (AP Photo/M. Spencer Green, File)

  • Jesse Jackson Jr., Sandi Jackson

    U.S. Rep. Jesse Jackson Jr., D-Ill., and his wife Chicago Alderman Sandi Jackson, thank family members at his election night party Tuesday, March 20, 2012, in Chicago after his Democratic primary win over challenger, former Rep. Debbie Halvorson, in the Illinois' 2nd District. (AP Photo/M. Spencer Green)

  • Jesse Jackson Jr., Sandi Jackson

    U.S. Rep. Jesse Jackson Jr., D-Ill., and his wife Chicago Alderman Sandi Jackson, embrace at his election night party Tuesday, March 20, 2012, in Chicago after his Democratic primary win over challenger, former Rep. Debbie Halvorson, in the Illinois' 2nd District. (AP Photo/M. Spencer Green)

  • Timothy Geithner, Jesse Jackson Jr.

    Treasury Secretary Timothy Geithner, right, declines an offer by U.S. Rep Jesse Jackson Jr., D-Ill., to talk to reporters during a tour of the Ford Motor Company Stamping Plant in Chicago Heights, Ill., Wednesday, April 4, 2012. (AP Photo/Charles Rex Arbogast)

  • U.S. Rep. Jesse Jackson Jr., Sandi Jackson

    U.S. Rep. Jesse Jackson Jr. and his wife, Chicago Alderman Sandi Jackson, ask each other for their support and votes as they arrive at a polling station for early voting, Friday, March 9, 2012, in Chicago. (AP Photo/M. Spencer Green)