I'd be happy with any of Frankie, Jake or Mark.
Frankie's a great dancer (though Kevin annoys me and I don't think their partnership is anything special), Jake's come from a non-dance background and I love his more reserved attitude to the show, plus I think he has a great partnership with Janette. Mark is annoying but the most improved, and I like Karen. Plus I have to admit I would find it hilarious to come on here afterwards if he wins given the wild sweeping grudge that seems to be held against him by a lot of people, many of whom like to conveniently ignore the fact that his background is no different to the almost universally-loved and never derided Kara. But I've posted at length about that before, as have others.
I can't take to Pixie - she seems sweet and she's a good dancer, but I find her partnership with Trent (and Trent in general) a bit annoying. Caroline is good but I think she's overrated, Simon is a dark horse but I haven't been that impressed with his ballroom yet, Sunetra's Latin is poor and Steve is the weakest dancer left in my opinion.