Rep. Jesse Jackson Jr. (Getty Images)
(USA TODAY) - Rep. Jesse Jackson Jr. resigned from Congress on Wednesday, ending a once-promising political career.
House Speaker John Boehner has received Jackson's letter of resignation, Boehner spokesman Michael Steel said.
Jackson, the son of the civil rights leader, was first elected in 1995. He has been on medical leave since mid-June and twice sought treatment at the Mayo Clinic for bipolar disorder.
The Democrat was easily re-elected to a ninth full term on Election Day, even though his constituents haven't seen or heard from him in months.
Once considered a rising star in the Democratic Party, Jackson is being investigated on allegations that he misused campaign funds to pay for redecorating his house and an expensive watch for a friend.
Jackson, 47, hired former federal prosecutor Dan Webb to work out a plea deal on the campaign finance allegations. CBS News said the deal would likely include jail time.
He also has been the subject of a long-running House Ethics Committee investigation stemming from allegations that he raised money for then-Illinois governor Rod Blagojevich in exchange for appointment to the U.S. Senate. Jackson denied wrongdoing in that investigation, which will now end. The panel does not retain authority over former House members.
Jackson's resignation will spark a special election in his Chicago-area House seat, a heavily Democratic enclave. Illinois state law requires that an election must beheld within 115 days after the seat is vacated.
Local news reports have said possible Democratic candidates include Cook County Chief Administrative Officer Robin Kelly, state Sen. Toi Hutchinson, and state Sen. Kwame Raoul, who holds the legislative seat once held by President Obama.