Tennessee congressional race becomes unlikely test of blue wave

Fresh off Democrats' domination in the off-year elections, a congressional race in Tennessee has become an unlikely test for whether a national blue wave is building that could produce a seismic shakeup in next year's midterm election.
The special election to fill the seat of retired Republican Rep. Mark Green, set for Tuesday, Dec. 2, was hardly on the national radar a month ago.
Now, the race between Democrat Aftyn Behn, a 36-year-old liberal state representative, and Republican Matt Van Epps, a combat veteran, has Democrat