First, his former best friend, and the husband of the woman that John Ensign f%$#ed, Doug Hampton, has been indicted for violating lobbying laws and conflict of interest laws.
The could get interesting if he decides to drop a dime on Ensign and the rest of his co-conspirators.
It does appear though that John Ensign is incredibly busted, since the normally toothless Senate Ethics committee voted to make a criminal referral to the DoJ, and the special prosecutor they appointed to investigated recommended that he be expelled from the Senate.
BTW, speaking of co-conspirators, it appears that Senator Coburn was hip deep in negotiating the specifics of the payoffs to Hampton and his wife.
Assuming that the Department of Justice has the stomach for it pulling on this string* will unravel a lot more than just a Senator boinking a staffer.
Pass the popcorn.
*I think that they don’t because of their mishandling of the Ted Stevens prosecution and because of a general Obama administration policy to let things slide when they involve Republican law breaking.