Mitch McConnell does not believe the bill can be sent to the president's desk due to inability to get cloture on a Dem filibuster. Even if he were to invoke some senate reconciliation rules or get past this, it will be vetoed by Obama.
Most think at this point, the GOP caves, funds Obamamnesty because they must fund DHS. They fear Obama will paint them as opposing funding for antiterrorism measures at a time when attacks like Charlie Hebdo are fresh in people's minds.
We didn't elect a GOP Congress for this.
When Obama invariably says he can't sign a bill that doesn't fund DHS "fully," he's counting on the stupidity of the American people to understand he's talking about funding the unconstitutional parts.
So, the GOP needs to send the hill up there, with the same amount of funding, just reallocate it so that the money that would have funded amnesty goes instead to more critical anti-terror measures. Then they can say that DHS is "fully-funded" we've just reallocated the unconstitutional parts to more critical, legal priorities.
But that's just me.