She only proved that you can't buy an election if you're outrageously blatant about it and a terrible candidate on top of that.

Most congresspeople spend more time raising money (banging the phones, attending fundraisers, etc) than they do on policy. You need a few million in the bank to be a "credible candidate", and lobbyists can get you a chunk of the way there.

I think she would have won if Brown weren't running -- in the end, he had a proven track record doing exactly the kind of reconstruction that California needs right now, and that trumped her money.

I'm not local and didn't have a great view of it. From what I heard, she was on the air so early and so obnoxiously often that it destroyed whatever message she may have had (and the message was lousy/stale/reactive, too). I think that loses to generic dem in California, but again I'm not local and don't really have the pulse there.

Yes, she could have used a few pages out of the following book:

Modern Vote Buying In The U.S., Koch , et al. 2000-

Er, surely Meg Whitman proved that Meg Whitman can't buy an election in California?

The fact that politicians go to great efforts to raise campaign funds proves that they think its worthwhile.

The reasoning you're looking for here is "necessary, but not sufficient".

This post is dedicated to mathematics.

If you do the 'good/bad' candidate, 'buys/doesn't buy' the election grid then a system that prevents bad candidates from buying elections would seem to be sufficient. All the other results are tolerable / unavoidable.