Sounds like it'd be a member of the Intelligence committee.
Assuming a California leaker, the possibilities would be:
House
Gary Condit (D)
Jerry Lewis (R)
Nancy Pelosi (D)(House whip)
Senate
Diane Feinstein (D)
If it's a leak, it'd be intended to be a means to give traction to the Democrats. That removes Condit and Lewis, leaving Feinstein and Pelosi.
Personally, I'm guessing Feinstein, as this has a Daschle-like smell to it.
The rats won't allow this to happen ( I presume it was leaked by a rat staffer to give their scoialist boss plausible deniability). Bush, Cheney and RUmmy should then go public and beat the rats like a rented mule over this.
I wonder if Condit should be allowed to stay on the Intelligence Committee since he is apparently not to remain in office. How tempting to "sell" our secrets. If he has done the stuff we hear about - he does not need to be in a place of trust. See - the Democrats don't really care about the security of the country or he would not be on that committee.