That would be beating Luther Strange in Alabama. Mitch McConnell is pulling out all the stops to get Strange back to the Senate because both Mo Brooks and Roy Moore oppose McConnell as leader. Strange is just another establishment hack and all the DC establishment hacks are going to bat for him.
The thing with Moore and Brooks is that Moore would be the more disruptive of the two, but the fact that Luther Strange is spending massive amounts of money to kill off Mo Brooks now suggests Strange fears Mo Brooks more than Moore.
I have a lot of friends who support Roy Moore, but it is worth noting that Strange and McConnell are both doing whatever they can to keep Mo Brooks out of a runoff. Their theory seems to be that Moore’s base may go to Mo Brooks, but no one else would join Moore. Moore is a rather polarizing figure.
That said, Moore is doing quite well and has a strong name ID and loyal base of supporters. The question is whether he can withstand all the money that is going to savage him in a runoff. The establishment has a vested interest in getting Luther Strange back to the Senate, which means you should have a vested interest in stopping him.
Mitch McConnell wants Luther Strange should be the campaign motto of either of Strange’s opponents. Do to McConnell in a Republican Primary what Republicans do to Nancy Pelosi in general elections and it could be the first step in ousting him as leader.