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I agree, if you're already running 6 to 7 miles, you'll have no trouble training up to the half. You do want to start to experiment with what you're going to take in for fuel during the race, a half is just long enough that you will need to take in something to keep from bonking. A gel or two works for me, but YMMV.
Be sure to allow for rest days and weeks.
Have fun!
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2007 Look Dura Ace
2010 Custom Tonic cross with discs, SRAM
2012 Moots YBB 2 x 10 Shimano XTR
2014 Soma B-Side SS