Seems to me that this statement is the key to why Bush doesn't want these documents out. Apparently, the Justice Department was thinking out loud about who it might prosecute and why. If the Department's targets were limited to the Clintons, I don't think Bush or Ashcroft would have any objection to the news coming out that, say, the Clintons almost got indicted for breaking fund-raising laws.
So my guess is that these documents also make references to other famous names, not necessarily all Democrats -- names that would embarrass both parties.