There are hints pulling it both ways. If the LA Times has solid evidence and is sitting on it, seems more likely its a Democrat. If Drudge knows about it but hasn't run it up the flagpole, it's most likely a Republican.
Larry Flynt seems ready to let something go on a Republican, from earlier posts. McConnell has been mentioned as the object.
His release timeframe is still a week or two away.
The LAT may be sitting on something involving a Dem.
The dilemma is how to sit on the story so they can both break at the same time, which helps the Dem, who will receive more favorable press than Mitch would.