They did the last Democratic president; and they feel even more strongly that this one is illegitimate, despite his thumping majority in the last election. Here's the scenario. The House GOP pushes for completely unserious Boehner plan (including a balanced budget amendment) that they know will be vetoed; they then filibuster the Reid plan in the Senate, forcing Obama to invoke a 14th Amendment executive prerogative, which they will then turn around and impeach him for.
Far-fetched? I hope so. But every time you think you have reached the end of Republican extremism, they manage to move further out of the solar system.
After watching today's events, I'm starting to have the same thoughts.