From John Allen a few days ago:
The case for Bergoglio in 2013 rests on four points.
First and most basically, he had strong support last time around, and some cardinals may think that they're getting another bite at the apple now.
Second, Bergoglio is a candidates who brings together the first world and the developing world in his own person. He's a Latin American with Italian roots, who studied in Germany. As a Jesuit he's a member of a truly international religious community, and his ties to Comunione e Liberazione make him part of another global network.
Third, Bergoglio still has appeal across the usual divides in the church, drawing respect from both conservatives and moderates for his keen pastoral sense, his intelligence, and his personal modesty. He's also seen as a genuinely spiritual soul, and a man of deep prayer.
"Only someone who has encountered mercy, who has been caressed by the tenderness of mercy, is happy and comfortable with the Lord," Bergoglio said in 2001. "I beg the theologians who are present not to turn me in to the Sant'Uffizio or the Inquisition; however, forcing things a bit, I dare to say that the privileged locus of the encounter is the caress of the mercy of Jesus Christ on my sin."
Fourth, he's also seen as a successful evangelist.
"We have to avoid the spiritual sickness of a self-referential church," Bergoglio said recently. "It's true that when you get out into the street, as happens to every man and woman, there can be accidents. However, if the church remains closed in on itself, self-referential, it gets old. Between a church that suffers accidents in the street, and a church that's sick because it's self-referential, I have no doubts about preferring the former."
...one Italian writer quoted an anonymous cardinal on March 2 as saying, "Four years of Bergoglio would be enough to change things."