Dems cannot let anything related to ACA pass. Doing so would be such a big trophy for the Tea Party to show off to the base that it would guarantee shut downs every time.
Depends. I agree that they cannot accept the House bill, but the Senate proposal is a straight give/take on ACA so I don't think that should be considered negotiating on the debt limit/CR. What I mean is, rather than "We'll give you income verification to end the shutdown" it's "We'll give you income verification if you give on the reinsurance tax" which is how negotiations should work (though I would prefer if Obama had simply refused to negotiate during shutdown)