CHICAGO  President-elect Barack Obama pledged Thursday to disclose any interaction between his transition team and the office of besieged Gov. Rod R. Blagojevich of Illinois, while declaring again that he and his staff had no involvement in deal-making over an appointment to his vacated Senate seat.

Federal officials also acknowledged that a grand jury was weighing evidence in the case against Mr. Blagojevich, though the timing of any indictment was unclear. Mr. Blagojevich was arrested Tuesday on charges of conspiracy and soliciting bribes in a case that involved, among other things, accusations that he had sought to put Mr. Obama’s seat in the Senate up for sale.

In a rare firsthand account of how Mr. Blagojevich, a two-term Democrat, went about the selection process, an Illinois state senator said in an interview that he had felt pressured to respond to the governor’s interest in him with a quid pro quo agreement and has withdrawn his name because of increasing wariness about the process.

The state senator, Kwame Raoul, who represents the South Side of Chicago, offered few details of his interaction with the governor’s office but said he received a call about a month ago confirming that he was under consideration. Soon afterward, however, Mr. Raoul said he ran head-on into another message: that the governor was looking for a candidate who offered something of tangible value to him.