A Senate staffer has confirmed to TPMmuckraker that the hold placed on the nomination of Neil Barofsky to be inspector general for the bailout has now been removed.

Politico had reported the removal of the hold earlier today, as we noted.

So now the focus is squarely on the identity of the GOP senator who placed the hold. And it now seems pretty clear, as we suspected from the start, that it was Jim Bunning of Kentucky.

According to the Senate staffer we spoke to, senators are working on the assumption that Bunning was responsible. And the staffer described a highly semantic argument that a Bunning aide made when asked about the issue, which would appear to only add to the evidence that Bunning was responsible.

The staffer said that a Bunning aide, speaking to an aide to another senator, tried to make the argument that technically, no hold had been placed, because there had been no request for unanimous consent on the floor of the Senate. A "UC request" would need to be made before calling for a voice vote on the issue, and it's at that point that the hold would officially go into effect. But in this case, Chris Dodd, the chair of the banking committee, had already been informed by the GOP cloakroom that one GOP senator wanted a hold put on -- which was what prompted Dodd to issue the statement that first revealed the existence of the hold.

The culprit is under no obligation, the Senate staffer said, to ever come clean. So we may never get official confirmation -- and the more important fact is that a vote on Barofsky's nomination is now set to proceed, probably by tomorrow, according to the staffer.

But at this point, the mystery seems all but cleared up.