Even if they impeach Lynch nothing happens. The Senate would never convict, and I doubt they would even be able to get the votes for impeachment in the House. Nobody would take a political risk like that this close to an election.
Start with Manchin in West Virginia and Angus King (I) of Maine, and build from there.
If the FBI report is really really bad, then make EVERY Democrat defend giving our highest secrets to our enemies.
-PJ