The funny thing about 2011 is that it looks a whole lot like 2008. Actually, in 2011, the Chargers are, technically, still in better shape than they were in 2008 when they trailed the Broncos by four games with four game remaining.
Now, the Chargers are last place in the division and need not only the Raiders to basically lose out, but need the Broncos and Chiefs to take nose dives as well.
To keep this short, let's look at how the Chargers beating out the Raiders.
Now, let's assume (huge assumption) that the Chargers win out and end the season 9-7.
Before playing the Chargers the last game of the season, the Raiders play the Dolphins, Packers, Lions and Chiefs.
The Raiders must travel to Miami, Green Bay and Kansas City. They stand a good chance to lose two, if not three of these games. Miami has played great at home, Green Bay is...Green Bay (cold) and Kansas City (really Cold) in December may be the toughest place to play in the league.
Now, the Chargers still need a lot of help, but nothing is impossible after watching that 2008 collapse of the Broncos.