Supporting actress is a very tight category. You can count out Ann Dowd, Kelly Reilly, Kerry Washington, and several other surprises.
There are four set nominees. But the fifth slot is the one that is up in the air. I still hold some hope for Samantha Barks. If Les Mis hits with voters she definitely could upset. However this is her first movie and she is competing against another actress in her own movie, who is a lock to win. Nicole Kidman has entered the race this week with surprise nominations in both the SAGs and the Globes. She is one of those performers that just usually comes up around Oscar time. I would predict that the fifth slot goes to Maggie Smith. It looks like Best Exotic Marigold Hotel has a shot at picture, she could be the acting representative from that ensemble. Plus the veteran actress was also the lead in Quartet, voters often reward for multiple roles.
The remaining four slots seem set. Despite missing out on an important SAG nomination I would not discount Amy Adams. However The Master is not a very strong contender and her role is not the largest. While Adams always seems up for an Oscar nomination she is one that is the weakest. I would say she is a lock with some vulnerability.
Helen Hunt will receive a nomination for The Sessions, the film does not have enough steam to carry her to a win. Lincoln may be successful enough to carry Sally Field to an upset. However although she is guaranteed her first nomination is decades, it is doubtful she will win the elusive third Oscar.
Of course the win seems to be guaranteed to go to Anne Hathaway. All of the marketing and buzz around Les Mis seems centered around her small but pivotal role. This is said to be the most emotional scene of the year and the tragedy of it should lead this consistent, but often overlooked performer to the gold.