There seems to be little common ground left in Washington if the tone on this Politico piece on the lame duck session is correct. If cooler heads don't prevail, we may be looking at the unraveling of the United States of America in very short order and that President Obama could be the last president of the 50 states.
For normal business to proceed, you need a majority of the House, a majority (often a super-majority to invoke cloture) of the Senate and the President to sign off on things. That may not be possible in the present political climate.
This other piece on immigration policy notes what could be the tipping point, a pending move by the president to basically stop deporting most people caught here illegally; that's a slight simplification, but not by too much. It's hard to make someone do something if there is no power to force them to move. Courts can make rulings but they require both an issue that they can rule on and have an executive branch willing to execute said ruling.
If the executive branch is unwilling to enforce the law, impeachment is an option that Congress has, if they they can get two-thirds of the Senate to convict. Turned around, 34 senators can enable the president to ignore the legislature if he has the funds to maintain the government.
If 34 of the 46 Senate Democrats returning stick with the president on immigration policy, one way to slow the President down is to stop funding the government. However, that requires a majority of at least one chamber of Congress to refuse to agree on a spending plan, which will become problematic as any government shutdown starts to bite and pressure placed on moderate Republicans to relent.
December 11th is the date that the current continuing resolution ends. A few days with laid off federal workers has been bearable in the past, but if those days turn into months and checks go unwritten, there could be some major chaos, one that could lead the president to try and rule by decree and ignore Congress altogether.
That sounds like some bad Glenn Beck nightmare, but we're not far from that if both sides lose a game of political chicken. Republicans are likely to "lose" by having enough "moderates" go along with a funding plan, but if neither side backs down, we could see the US cease to function, reverting back to 50 state governments that will still operate in the absence of a federal government.