Chairman Jo Bonner, R-Ala., and ranking Democrat Linda Sanchez of California said the panel voted Oct. 13 to end its temporary deferral of the case that had been requested by the Justice Department. The department has withdrawn its request.
Jackson, D-Ill., has denied wrongdoing and has not been charged with any wrongdoing. The case was deferred in September 2009.
While the future course of the investigation is not clear, the committee has looked at whether Jackson, or someone acting on his behalf, offered to raise funds for then-Illinois Gov. Rod Blagojevich in return for an appointment to the Senate seat.
Jackson, the son of civil rights leader Jesse Jackson, is in his ninth term. He was elected in 2010 with 81 percent of the vote.
Blagojevich, who won two terms as Illinois governor, was convicted last June of a wide range of corruption charges, including trying to sell the Senate seat.
Jackson has acknowledged he was "Senate Candidate A" in the Blagojevich criminal complaint, one of several candidates whom authorities say the former governor considered for the seat.
The congressman's chief of staff, Rick Bryant, said the office had no comment on the announcement.Jackson's attorney, Reid Weingarten, did not immediately return a call seeking comment. Kim Nerheim, a spokeswoman for the U.S. attorney's office in Chicago, declined to comment on whether the Justice Department has closed its probe of Jackson.
The committee statement said the extension "does not itself indicate that any violation has occurred, or reflect any judgment on behalf of the committee."
The statement said the committee would announce its course of action by Dec. 2.
According to the criminal complaint, Jackson's supporters were willing to raise $1.5 million for Blagojevich if he picked the congressman.
Jackson said in September 2009: "As I've said from the beginning, I have done nothing wrong, nor have I been accused of doing anything wrong. Everyone knew that I was interested in the Senate appointment. I was deeply honored and humbled to receive the support of public officials, organizations and citizens from across the state. My efforts and actions were all public, ethical and legal."
Jackson's alleged use of staff was in a report by the Office of Congressional Ethics, which reviews potential ethical violations by House members and staff and refers cases to the ethics committee of five Democrats and five Republicans.