The Republican establishment won big during this year's midterm elections, fending off far-right candidates in primary races who might have threatened the party's bid to retake full control of Congress. 2016 will be tougher. GOP leaders will have to keep an eye on a wide-open presidential primary, along with internal party fights at the House, Senate and gubernatorial levels. That could spread the party thin and leave an opening for conservative activists to pluck off establishment leaders with greater ease, particularly in congressional races as much of the attention shifts to the battle for the White House. Conservatives, smarting from their losses this cycle, are already getting organized for 2016. And they came out of this month's government spending fight furious that congressional Republicans produced no tangible response to President Barack Obama's immigration executive action and convinced that Republicans are still ceding issues to Democrats after the election.
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The Tea Party lost nearly every one of its battles in 2014, but may have a better shot this cycle
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With three levels of primary fights, the establishment's attention and resources will be split
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Establishment groups are already gearing up for another costly and divisive battle
Though they will hold majorities in both chambers, Republicans face a daunting map in the @placeholder, where they'll defend 24 seats in 2016 -- seven in states that Obama won twice.