I am an Obama supporter who is, to a certain degree, willing to concede the experience issue. Basically, I would argue that it is hard to know how much experience she got by having her spouse be President without knowing how engaged she was with what he was doing. However, given their similar backgrounds and interests…and the fact that she did work on one particular aspect of his policy (health care), my guess is that she was pretty engaged and was thus likely to have picked up some experience.
As an example, if I look at my girlfriend and ask to what extent she has gotten the experience doing my job as a physicist osmotically through going out with me, I would have to say close to zero. However, this is for a number of reasons: Because she has a very different background than me, I don’t share with her much about the details of work…To the extent I do tell her things, they are very abstracted and have more to do with the interactions with other people than the calculations themselves. Furthermore, my job is very much a 9-to-5 job and so my work life and home life do not intermix very much.
However, if things were very different, e.g., my girlfriend had a substantial physics background and she had to attend a lot of functions related to my job, such as technical talks that I gave and I could even ask her for help on technical problems I ran into with my research, then in fact, I think she could gain quite a bit of experience through me even if it still would be different from firsthand experience.
My guess is that Hillary’s case is much closer to my second example and therefore that she has probably gained at least some, maybe even a fair bit, of useful experience for the Presidency by being First Lady for 8 years.
However, in the end, I don’t really know if experience is all that important in being a good President. After all, we have a Vice President (who has been, in many regards, probably almost a co-President) who touted his experience (both in government, particularly in foreign and defense policy, and in a leadership position of being a CEO of a major corporation) but who is atrociously bad because of extremely bad judgement and ideological blindness.
I find Obama’s arguments that vision and good judgement are probably more important than experience (at least beyond a minimum level of experience that, e.g., anyone in national public policy would get) to be pretty compelling.