Use you're head. If the Republicans lose control of the house in November, the Democrats will gain control of the house. Do you honestly think that the Democrats holding the house is going to benefit anyone?
It is the only chance for the Republicans to find their way back to the conservative side. That is more important than one election cycle. If the Republicans stay in control, there will be a further move to the left, they are already farther that direction than most Democrats were in the 60's.