I voted the Chiefs. I don't necessarily think they are the best team of the bunch, but I think they have the path of least resistance. The Broncos look bad on paper, no Dumervil, possible hamstring tear at last check, and who was pretty darn mediocre when healthy anyways, and no Brandon Marshall. Sorry, but Jabar Gaffney the number 1 looks pretty bad, and if Moreno misses time at RB, how much faith does anyone have in Buckhalter? So that might be two bingo squares.
The Raiders look improved, plugging in Campbell at QB instead of Russell/Gradkowski is a huge ugrade. The receiving core looks pretty putrid, but Zach Miller should prove a nice receiving threat. The defense is a question mark, so the Chiefs have a shot at two wins in the division there as well, not a lock, but a shot.
That leaves the obvious class of the division, the SD Chargers. No V-Jax, McNeil holding out, and a rookie RB, albeit one I like a lot. Like just about every other team, one QB injury away from falling down numerous pegs. Even if healthy, and as the class of the division, the possibility remains the Chiefs could steal a game away from the Chargers.