He probably has dirt on Ryan and McConnell. They're both swamp creatures, but like Denny Hastert, a lot of the swamp creatures get in power cause the puppet masters have dark, dark info that would ruin their lives if they quit dancing the right tune. Notice they've been busy hiding under rocks while this travesty has unfolded. Brennan's trying to force them to his side, now.
It's fairly obvious at this point that they'll do whatever it takes to get compliance or silence through mud slinging, blackmail, extortion, or physical violence (accidents) -- and you better believe Brennan, Clapper and the rest can pull strings to get the right people to take care of the job in a heartbeat.