Yes, it will take you to within a couple miles of the start of the Roan climb, which is 7 miles itself, and culminates at Carver's Gap which is the top. But, I have not ridden on Hughes and don't know if its paved. On the Roan event itself, you turn on 143 from 19E and don't ride Hughes Gap.
Roan is a great climb, and I highly recommend the event at the end of this month. The entire route is nice, almost storybook in some respects. The Roan descent back into Bakersville is about as nice a decent as you will find in these parts.