From the New York Times:

Federal authorities on Wednesday identified Democratic Representative Jesse Jackson Jr. of Illinois as the potential United States Senate candidate who was portrayed in court papers made public Tuesday as being the most deeply enmeshed in the alleged scheme by Gov. Rod Blagojevich to benefit from his appointment of a new senator to the seat vacated by President-elect Barack Obama…

Mr. Jackson, who has publicly sought the appointment, said he met with Mr. Blagojevich to discuss the job for the first time earlier this week, after not having spoken to him for more than four years. Mr. Jackson said he never authorized anyone to offer anything in return for the appointment. Mr. Jackson, the son of the civil rights leader, was first named by ABC News as the person identified in the criminal complaint as Candidate 5. “It is impossible for someone on my behalf to have a conversation that would suggest any type of quid pro quo or any payments or offers,” Mr. Jackson said in comments broadcast by ABC News. “An impossibility to an absolute certainty.”

The identify of Candidate 5 has been a mystery since the filing of a legal complaint on Tuesday accusing Mr. Blagojevich and an aide of engaging in corruption and conspiracy, stemming in part from an alleged effort by the Governor to sell off Mr. Obama’s seat in return for campaign contributions and lucrative jobs for Mr. Blagojevich and his family. Of the six candidates for the senate seat who are identified by number in the complaint, but not named, only Candidate 5 is said to have engaged in possible wrongdoing by engaging in discussions through an emissary about a possible quid pro quo with Mr. Blagojevich’s camp. The emissary was also not identified by name.

Jesse Jackson, Sr., of course, has a long history of cutting curious deals with his political organizations’ donors, including Citigroup, Freddie Mac and Verizon.