The triple champion currently holds a 118-point advantage over Martin, with Gordon a further 32 back.
But both rivals are hopeful that the risks of being caught in a shunt at Talladega - as happened to all three drivers in the season's earlier visit to the track - could help them profit over Johnson.
"This is the biggest opportunity for all of us," said Martin. "I would assume [Johnson] would go into this race uptight like I always have. But I'm not because it really doesn't matter either way for us because we can't do anything about it anyway, so we might as well just go out there and have some fun with it. That's my approach."
Gordon, who trails by 150 points, still believes he is in the hunt for the title but admits his results alone will not be enough to threaten Johnson.
"We're not counting ourselves out of this thing by all means, but obviously some things have to happen in order to get us back in it. Those are things that are not in our control," said Gordon.
"Whatever is meant to happen is going to happen. All you can do is go out and work really hard. We just go out there and try to put ourselves in the best position and hopefully that's a win."
Primera Liga round-upJohnson aiming to defend points lead
