Adam Bonica expects the 112th Congress to be the most polarized in recent memory:
The hollowing out of the political center explained the momentous rise in polarization during the Southern realignment. Now that only a handful of moderates remain in the House, polarization can no longer be portrayed as a story of vanishing moderates. It appears the rise of the extremists has stepped up as the driving force behind congressional polarization.
Yglesias analyzes.
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