Out of the people that are still left in Total Drama Action as of Ocean's Eight - or Nine, Duncan, Harold, Leshawna, Heather, Beth, Courtney, Justin, Lindsay, I think the favorite to win is Heather, but I just know they're going to prove me wrong.
As much as people don't want to admit it, Heather's become more of an anti-hero and pretty much one of the good guys as of Ocean's Eight or Nine. She's begun putting everything she's got into challenges lately without any alliances.
Plus, there are certain patterns as of the current episode that have been keeping true:
The underdog team [Grips/Bass] eliminates people, then the other team eliminates just as many; then the underdog team is the last to eliminate someone [let's face it, with 8 people, they can't vote anyone else off and nobody else is coming back].
Also, has anyone noticed that, besides DJ, they've been eliminating couples only: Bridgette/Geoff, Trent/Gwen, even Izzy/Owen and they've all been back-to-back [besides Izzy's first elimination. With that logic, unless Duncan and Courtney break up, the odds are against them [although the odds were against Courtney when she first came to season 2] and seeing as Leshawna is also hated by her entire team, her odds of winning aren't that great, so if she loses, then, with the logic of couples only, Harold will be next.
Beth and Lindsay are the lackeys, they really don't have a chance of winning... and lackeys bring me to my next point:
The villain of the series will get to the final 3, but won't win. This season, it applies to two people: Justin and Courtney; Heather was a villain in Total Drama Island, but not so much this season. Besides looks, however, Justin doesn't seem to have much going for him anymore; I don't think he'll even make it to the final 3. Courtney, however, seems to be taking Heather's spot and this puts the odds against her even more.
Finally, the pattern of elimination after the merge is underdog, then other team. Last time, there were 6 from the Gophers, which is why the final 3 was all Gophers, but this time it's even 4 to 4; so if this pattern continues, then one person from the Killer Grips will make it and two from the Screaming Gaffers will make it. This gives everyone in the Screaming Gaffers (including Heather) [not to mention that a Gopher won last time] more of a chance than the Grips.
Also, the fact that a guy won last time, means that they might have a girl win this time.
Now, if you'll excuse me, I'm going to build a brick wall against the Heather-haters that I know are going to attack me...