Kevin Drum has it in one short sentence:
The Republican Party is bending its entire will, staking its very soul, fighting to its last breath, in service of a crusade to….
Make sure that the working poor don’t have access to affordable health care.
He goes on to say:
I just thought I’d mention that in plain language, since it seems to get lost in the fog fairly often. But that’s it. That’s what’s happening. They have been driven mad by the thought that rich people will see their taxes go up slightly in order to help non-rich people get decent access to medical care.
I have exceeded my blockquoting limit here, but I can’t say it any better or more succinctly than that. The Republican Party can’t stand the thought of its side paying taxes which might go to help people on the other side have a more decent life.