This big (can't remember how many?) can of worms has been opened and there's no closing it. McCain's campaign panicked today and tried to throw everything, including the kitchen sink, back at Barack Obama.
What's at issue here is the McCain's inherited wealth and how that will influence his policies as President. McCain has already flipped flopped on tax cuts for the wealthy, proposed an economic tax plan giving billions to corporations, and what's worse is McCain has previously brushed aside the concerns of the economy while his economic advisor called Americans a bunch of whiners.
As duly noted, the topic of a candidates wealth was made into a very large issue in 2004 against John and Teresa Kerry. John was teased for windsurfing while Teresa was battered for months to disclose her financial records, which she finally did.