He won a convincing victory in 2004, defeating two Democrats with a slim majority of the vote, to succeed John Breaux (D).
Palfrey, 51, titillated national media this spring by threatening to auction her list of clients' phone numbers to the highest bidder.
A day later, on April 27, Tobias resigned from the State Department, reigniting the media firestorm over Palfrey's records.
That was seemingly snuffed out by Kessler's temporary restraining order two weeks later, but Kessler vacated her order on Thursday, clearing the way for Palfrey to post the records online.
The service's proprietor, Deborah Jeane Palfrey, 51, faces federal charges of racketeering for allegedly running a prostitution ring out of homes and hotel rooms in the Washington area.