Technically the Campbell Award is not a Hugo Award, although I couldn't tell you why that is. It's voted on alongside all the other Hugos, and I've actually read enough excellent new authors recently to make Campbell recommendations this year.
Here in alphabetical order are the new authors I am planning to nominate. I'm also listing in parentheses a story I particularly enjoyed by each one, to give you a place to start if you care to check out their work:
Gwendolyn Clare ("Iron Oxide Red," Daily SF)
Keffy R.M. Kehrli ("Advertising at the End of the World," Apex)
Malinda Lo (Ash)
Ferrett Steinmetz ("As Below, So Above," Beneath Ceaseless Skies)
Brad R. Torgersen ("Exanastasis," Writers of the Future, Vol. 26)
Except for Malinda Lo, all of these authors have to date focused on short fiction -- I confess I haven't read some of the new novelists who have been getting a lot of buzz, such as Lauren Beukes and Dexter Palmer -- and they all do it so well I would love to see some of them on the ballot.
UPDATE: I was poking around other folks' recommendations on the web, one of which suggested Malinda Lo for the Campbell. She is not on the Writertopia list of Campbell-eligible authors, but I can't figure why not -- I believe her first genre publication was Ash in 2009. Ash was an outstanding novel, so I'm adding her to my Campbell list. Unfortunately, that means someone else has to be bumped, so apologies to Monica Byrne, who still has a great future ahead of her.