Argument starter: the two tiers of championship contenders

We're coming up on the halfway point of the season, and it's time to start speculating. What do we know so far? We know that Jimmie Johnson's not invulnerable. We know that Denny Hamlin is legit. And we know that there are plenty of drivers who, to put it simply, just don't have a shot this year.

So let's start a little talk. At this point, there are probably 16 drivers with a legitimate shot of making the Chase, maybe even 20. But as for guys who could honestly win the championship? I'm saying there are only six. And those six aren't even equal. I'm thinking we've got two separate tiers of contenders here, and they break down like so:

Tier 1: Jimmie Johnson, Denny Hamlin, Kyle Busch. These three guys can win the championship all by themselves. Their teams work in sync, they can turn it on and win a race at almost any track. Any one of them can get hot at any time.

Tier 2: Kevin Harvick, Jeff Gordon, Kurt Busch. These cats need help from the guys above them. More specifically, they need the guys above them to falter. Tier 2, for the most part, can't outrun Tier 1 heads-up over the course of a 10-race Chase.

Now, there's plenty of room for argument here. Yes, Harvick is atop the standings at the moment. And yes, this list leaves out notable drivers like Matt Kenseth and Tony Stewart. And yes, maybe the Busch brothers ought to switch places on this list. But hey, that's what this post is all about — stirring the pot, starting the discussion.

So what's your take? Anybody you'd add to these lists? Anybody you'd remove? Have at it. Even you, Junior fans.