In the beginning, the play seems to be biased toward Nora. We're definitely asked to sympathize with her—for good reason, as it's pretty hard to be on Torvald's side. From the moment he gets on her case about eating macaroons, we know that he's overbearing, even for a Victorian-era dude. His demeaning little pet names for Nora don't help his case.
To Ibsen's credit, however, Torvald does seem to be redeemed in the end. His last line, "The most wonderful thing of all?" (3.381), indicates that he's gone through—or at least is heading toward—the same spiritual awakening as Nora.
And we go from seeing Nora as Torvald's prisoner to seeing that all the characters, Torvald included, have been prisoners in some way. In the end, the tone of the play becomes more objective. Sympathy can be found for all its characters. That kind of ultimate objectivity is one of the reasons that Ibsen is still a huge deal... even though he died way back in 1906.