The GOP will take over both chambers of Congress on Jan. 6, with issues like the Keystone XL pipeline, Obamacare and immigration reform likely to take priority.
The president's action, to be announced later today, will grant temporary relief to some immigrants living in the U.S. illegally. Republicans could strip away funds that would go toward Obama's plan.
Democrats see an opportunity in the South's changing demographics — particularly in states with growing Hispanic communities, lots of unregistered black voters and migration from other states.